Heavy
Marisa (Fire Emblem: The Sacred Stones) vs White Fiend (Lunar: Eternal Blue)
WF 2HKOs with MT after the buff, but has issues with Marisa's evasion. Call it 1+5=6 turns to get the 2 hits in as a kneejerk? 1+4=5 turns if the evade is disrespected a bit. Alternatively WF can just spam Frost Breath for a MT 3HKO, but this is only worthwhile if you see this as turning off Marisa's doubles, which I don't think I would. I think Marisa 8HKOs WF with a Silver Sword if she doesn't crit. So yeah, that's 4 turns. WF really needs to have Frost Breath turns count as sufficiently "fast" to stop the doubling.
Middle
Daoros (Shadow Hearts: From the New World) vs White Mage (Final Fantasy V)
In retrospect, both of these kinda low Heavies. Anyway. Seems to be all about if Daoros can kill on his 2nd turn combo. Daoros attacks, WM opens Safe (and eat a counter-buff and hope it isn't offense or speed), Daoros hopes to kill on attack->spell through the buff. If he doesn't, though, and WM survives to heal, he's in deep. I suspect Daoros manages the double KO though, which means WM is heal-locked, and he probably deserves the tiebreak since even if he doesn't, if he gets the right counter-buff he wins anyway.
Light
Jakob (Fire Emblem Fates) vs Io Nitta (Devil Survivor 2)
Tomebreaker is a problem here. Io can go Berserk to get around it... but... now Steel Shuriken is a problem, since I'd probably see it debuffing all the hits in a multihit attack like this (e.g. multi-hit kinda like Brave Weaponry). This means Io is really gonna struggle to 3HKO here, and even that might not be enough with the self-damage.
Camille (Celestian Tale: Old North) vs Judith (Tales of Vesperia)
No ToV, but just from the stat topics, Camille should 3HKO and be faster, so it's all about Judy 2HKOing.