Wyatt’s scintillating 59 from 38 balls meant she overhauled fellow England star Tammy Beaumont at the top of the standings with 295 runs in total.
Freya Kemp’s 31 and Georgia Adams’ 27 lent support as the Brave piled up 139 for six on a dry pitch, despite three for 21 for England seamer Kate Cross.
Jemimah Rodrigues, starved of strike for long periods, made 24 in the chase, but Kalea Moore returned three for 15 and Lauren Bell three for 21, while there were a trio of stumpings for Rhianna Southby as Superchargers were bowled out for 105.
It meant the Brave, bridesmaids in the first two finals, finally got their hands on the trophy, a fitting end to a glittering career for retiring skipper Shrubsole, who took the match-clinching wicket in England’s World Cup winning triumph against India at the home of cricket six years ago.
Much of the Brave’s success on the run to the final had been built on the triumvirate of Smriti Mandhana, Wyatt and Maia Bouchier, but after being put in, two were gone in the blink of an eye.
Mandhana dismissed the first ball of the match to the point boundary only to slice the next from Grace Ballinger to fly-slip, while Bouchier played too soon at one from Cross to leave the Brave eight for two.
However, Wyatt produced a gem of an innings as the England batter played shots all around the wicket, sweeping effectively and hitting inside out over the off-side in racing to 50 from 35 balls with nine fours. A glorious straight six followed as she and Adams added 84 in 63 balls.
A mix-up meant Cross’ underarm throw ended Wyatt’s knock prematurely and Adams, dropped earlier by Georgia Wareham, holed out to the same fielder for 27.
An extraordinary cameo from Kemp, including swinging the bat out of her hands, lifted the Brave above par before she and Chloe Tryon both fell in Cross’ excellent final set.
Marie Kelly was given out lbw to the first ball of the chase from Bell, only to be reprieved on review, but undeterred the England speedster bowled her off the pads with the second.
Phoebe Litchfield took up the chase with two dismissive early fours in a bid to overhaul Wyatt once more as leading runscorer.
She would though only get to 13 before swinging another Bell delivery to a catcher in the deep.
Rodrigues picked up five from a misdirected Tryon throw at the stumps, but only 28 came from the powerplay.
Wicketkeeper Southby then took centre-stage with two brilliant pieces of glovework to stump first Hollie Armitage and then England newbie Bess Heath, the latter having previously hit Bell over the ropes for six.
Shrubsole joined in the fun with a farewell wicket of Alice Davidson-Richards and once Rodrigues holed out in the increasingly desperate pursuit of boundaries, Brave were all but home.
Matthews, who has been enjoying superb form for the Welsh Fire, was again on song, as she captured 4-14 in 20 balls to restrict Southern Brave to 103 before hammering an unbeaten 26-ball 35 to get her franchise across the line at 106-1 with 26 balls to spare. Captain Tammy Beaumont was also left unbeaten as she topscored with 59 off 40 deliveries.
With the win, Welsh Fire are now in a strong position, due to their superior net run rate, to finish in top spot and qualify automatically for the Hundred final at Lord's on Sunday. Oval Invincibles require a convincing win over Trent Rockets on Wednesday afternoon to leapfrog them.
Scores: Southern Brave 103 all out (100 balls); Welsh Fire 106-1 (74 balls)
“I think we've been really good. When you look at our line-up, we've got a lot of experience, and we've played on that really well,” Matthews said in a post-game interview.
“The bowlers have done a really good job at making sure we don't have to chase too big of a total. I think it's been a complete team performance, and that's where we've performed really well; everyone's been chipping in and playing their role,” she added.
After Beaumont inserted Southern Brave at the toss, Matthews dismissed the in-form Danni Wyatt (two), caught at deep midwicket, before Smriti Mandhana (one) departed four balls later to the pace of Shabnim Ismail to leave the Brave 15 for 2 at the end of the PowerPlay.
Whatever hopes Southern Brave had of repairing the damage were dashed when Jess Jonassen had Georgia Adams (six) stumped. Maia Bouchier (10) was Matthews’ second scalp, brilliantly caught by Phoebe Franklin in the deep, before Freya Kemp (two) knicked one behind to give Jonassen her second wicket.
Matthews got her third when she bowled Naomi Dattani (two) and then completed her allotment with the scalp of Kalea Moore (zero), as Southern Brave were in totters at 47 for 7.
Chloe Tyron was the only bright spark of the innings, as she posted an aggressive 38-ball 55, including seven fours and a solitary six at the backend, as she dominated a 52-run eight-wicket stand with wicketkeeper Rhianna Southby (15).
Matthews’ haul was supported by Jess Jonassen (3-21) and Freya Davies (2-14).
Despite losing Sophia Dunkley (seven) to Lauren Bell early, the result was never in doubt for Welsh Fire, as Beaumont was especially strong on anything loose, working the field with sweeps and cuts, while Matthews picked the gaps behind square in a 72-run stand off a mere 54 balls.
Beaumont raised her half-century in just 31 balls in a knock that had 10 boundaries, while the Barbadian, Matthews, struck five boundaries in her knock as Welsh Fire continue to blaze heading into the business end of the tournament.
After winning the toss and batting first, the Rockets posted 126-8 from their 100 balls.
Openers Tom Banton and Adam Lyth gave the Rockets a good start with a partnership of 46 for the first wicket before both went in quick succession for 30 and 16, respectively.
A series of starts from Alex Hales (15), Joe Root (16), Rovman Powell (16) and captain Lewis Gregory (19) propelled the Rockets to their score.
Chris Jordan was the pick of the bowlers for the Brave with 3-22 from his 20 balls while Jofra Archer and Danny Briggs took two wickets, each.
The Brave then needed 99 balls to reach 127-8 and secure victory.
After a 43-run opening partnership between Alex Davies and captain James Vince, the Brave lost a cluster of wickets very quickly, eventually struggling at 78-6, needing 49 from 20 balls.
Kieron Pollard, who at that point has scored six off 14 balls, faced up to Rashid Khan in a crucial set of five to likely determine the outcome of the game.
The former West Indies captain then produced one of the most brutal displays of hitting of his career, belting Khan for five sixes in a row to put the Brave firmly in control, now needing 19 from 15 for victory.
The momentum continued in the way of the brave as the next set of five balls went for 10 runs to leave the Brave needing nine runs off 10 balls.
Pollard’s innings came to an end off the first ball of the next set for a 23-ball 45 including two fours and five sixes, bringing Jofra Archer to the crease to join Chris Jordan.
With the Brave eventually needing four runs off two balls, Jordan hit Lewis Gregory for four over square leg to secure the win.
The Brave, after winning the toss and electing to bat, posted 146-8 off their 100 balls thanks to a 22-ball 37 from former West Indies captain Kieron Pollard and cameos of 28 and 26 from Alex Davies and James Coles, respectively.
Callum Parkinson took 2-38 from his 20 balls of left-arm spin for the Superchargers.
The Superchargers then needed only 85 balls to reach 147-3 and secure their first win of the season.
Pooran than led the successful chase with 62 off 34 balls including four fours and five sixes while captain Harry Brook finished 34* off 20 balls including four fours and a six.
Opener Graham Clark also chipped in with 27.
Akeal Hosein took 1-19 off 15 balls for the Brave.
Full Scores:
Southern Brave 146-8 off 100 balls (Kieron Pollard 37, Alex Davies 28, James Coles 26, Callum Parkinson 2-38)
Northern Superchargers 147-3 off 85 balls (Nicholas Pooran 62, Harry Brook 34*, Graham Clark 27, Akeal Hosein 1-19, Jofra Archer 1-19)
Russell, 34, smashed an unbeaten 23-ball 64 that included six fours and five sixes in Manchester Originals' mammoth score of 188-2. He was given the perfect platform after openers Joss Buttler (68) and Phil Salt (34) gave the side a solid start with a stand of 64.
Buttler clubbed three fours and five sixes in his 42-ball knock while Salt found the boundary ropes on four occasions and cleared it once is his innings that lasted 22 balls. However, while both knocks were impressive, they paled in comparison to the mayhem that Russell produced scoring at a rate of 278 per cent to drive Manchester to within 12 runs of the 200 mark.
Jake Lintott, who dismissed Salt was the best of the Brave bowlers with 1-28 from 20 balls while Michael Hogan took Buttler’s wicket to finish with 1-48 from his 20 ball allotment.
Faced with a daunting target, Southampton crumbled under the scoreboard pressure, capitulating to 120 all out.
Openers Quinton de Kock (21) and James Vince (20) gave them a good enough platform with an opening stand of 36 but Southampton Brave were simply unable to maintain the scoring rate of 1.88 runs per ball.
George Garton’s 25 from 14 balls and Ross Whiteley 21 from 12 attempted a short-lived late-order revival that would invariably come to nought.
Russell picked up the wicket of the dangerous Tim David, who made a run-a-ball 10 to finish with figures of 1-7 from five balls.
It was Paul Walter, though, who did the most damage with 3-20 from 15 balls. Mark Pattinson and Tristan Stubbs took two wickets each for the Manchester Originals.
For his heroic efforts with bat and ball, Russell was named Player of the Match.
