What’s your opinion on the victors also?
Kiryu beats Shizuo low/mid diff. Kiryu is generally more skilled, faster, and has better AP and his heat and passive abilities would give him a huge leg up, but Shizuo is no slouch and his ridiculous lifting strength compared to Kiryu could cause some trouble.
Yagami beats Wei low/mid diff, Yagami generally outpaces Wei in terms of speed by a wide margin, and is arguably more skilled then Wei due to a knowledge of multiple styles, his magicalso generally beats out Wei's magic and most of the weaponry at Wei's disposal. The only things that pose a major threat would be rocket launchers (for obv reasons) and the fact Wei has Agent 47's ******* Silverballer, which absolutely could one shot Yagami if he lands a shot with it, but due to the speed advantage and crazy magic that's unlikely.
Majima beats Undyne mid diff, while he outstats pretty substantially (I hear there's some debate on if Undyne gets Undying form, she might match up a bit better then due to multipliers) and Undyne's soul manip/danmaku could catch Majima off guard, his greater speed, higher AP, greater combat variety due to his variety of combat styles & weapons, the ability to overwhelm Undyne with shadow clones, and paralysis inducement.
Majima either beats Setsuna very high diff or loses, depends on if you think his speed advantage (Hypersonic compared to Setsuna's Supersonic) could allow him to get off a paralysis inducement could net him a chance to close the AP/durability gap between them, as Setsuna is 8B compared to Majima's 8C, but paralysis inducement into a throat slash/fatal stab could still spell Setsuna's end.
Majima vs Juri, I've put less research into I'm not familiar with SF lore, but it seems dependent on which version of Juri you use. If you use her at her full power with the Feng Shui Engine from SF4, she's faster than Majima at High Hypersonic against his Hypersonic, and has 8B AP/Durability compared to Majima's 8C, which would likely outpace and kill him, outside of a lucky paralysis inducement and maybe overwhelming her with shadow clones, Juri would probably take that. HOWEVER it seems she loses the Feng Shui Engine after SF4 and has to use a much less powerful Alpha version going forwards, which seems to cap her AP out at 9A, with Superhuman speed regularly, but Subsonic+ bursts of speed & combat reactions. Majima would easily be able to take her out via higher AP, much higher speed, shadow clone overwhelming, and paralysis inducement.
tldr, he stomps current Feng Shui Engine Alpha Juri, but likely loses to original full power Feng Shui Engine Juri outside of a lucky shot.
Also just to throw in an extra matchup:
Ichiban vs Josuke Higashikata from Jojo is his big matchup rn I think. This matchup kind of varies wildly depending on a single feat, and has some interesting stuff going into it. So Ichiban in base is actually stronger and faster, with Josuke's speed being peak human with Relatavistic+ reactions, while Ichiban has hypersonic reactions and combat speed (and one lightning speed attack due to... attacking with actual lightning), he's definitely outpacing Josuke himself, but the big thing is his stand. His stand is Relatavistic+, with a Speed of Light reaction due to tagging another SoL stand. He can also potentially reach FTL speeds, but its situational and dependent on his distance from Josuke in the first place. Josuke himself would not be able to take a hit from Ichiban due to his higher AP, and even if his stand hit Ichiban, they're both comparable in AP and it wouldn't kill him, due to both being building level. The fight could generally come down to if Ichiban could speed blitz and take out Josuke before he materializes his stand, or if he'd be able to hang in against Josuke for long enough after summoning it to get in a definitive finishing blow, which is arguable due to Ichiban's myriad of different weapons and classes and styles, not to mention his summons, and the ways he has to keep in the battle with his healing items and effects like being able to survive a fatal blow. It's also arguable that Ichiban could see and directly combat Josuke's stand, due to him being able to see and interact with spirits in the real world, and downscaling from Kiryu, who was able to physically punch and put spirits to rest with his bare hands.
HOWEVER Josuke does have some wincons. For one, the Speed of Light tagging his stand pulled off definitely outclasses Ichiban's speed, and he could potentially beat down Ichiban in time before he could seal the deal on Josuke. It also seems that when Josuke is enraged he can bypass conventional durability by fusing people together with other objects, which would bypass Ichiban's durability. The argument could generally go either way..... but....
What throws a wrench in this MU is if you buy the Satellite laser or not. The satellite laser is.... interesting, as its pretty hard to deny that it exists and is real, Ichiban should realistically be able to summon the satellite laser and hit his opponent with it, which based on calculations, would likely be somewhere in Tier 6 based on it splitting clouds the way it did. This is obviously, far, far beyond Josuke's pedigree and would kill him instantly. I'd say he has a pretty solid wincon on this front, if he's in danger of death, pulling back and just dropping a satellite laser on Josuke would absolutely do the job and put him under. However, scaling Ichiban (or any Yakuza character for that matter) to the laser itself is ABSOLUTELY preposterous. It's the definition of an outlier and Tier 6 Yakuza, as incredibly based as that sounds, should not be scaled to every character. It belongs EXPLICITLY to this ONE summon that Ichiban has.
So yeah, I lean towards Ichi taking this matchup, he has greater variety, could debatably see Josuke's stand, some interesting gimmicks to keep him in the game longer, summons to help him out, obviously outclasses Josuke physically and can at least match his stands' regular output, though would struggle with its higher speeds, and if using the Satellite laser, has an easy instant kill method available at the press of a button. However he absolutely could be killed via being outpaced by Josuke's stand at its higher end speeds and killed with its dura negging abilities.