Godlike
X (Mega Man X: Command Mission) vs Yunalesca (Final Fantasy X): Yunalesca has the HP for this, and X can't handle her tricks. Absorb, X can't get zombied before next turn (needs to OHKO form 1 without hyper mode... yeah no), Absorb, anything.
Kusuha Mizuha (Super Robot Taisen Series) vs Dark Force (Phantasy Star Series): Kusuha can probably manage this? Guard spam + high HP means she probably lasts quite a while, and her damage was fine.
Epsilon (Mega Man X: Command Mission) vs Celes Cher (Final Fantasy VI): What Monkey said + Epsilon's damage is ITD so it outraces Cure even if Celes somehow could escape the lock.
Heavy
Zero (Mega Man X: Command Mission) vs Hugo (Suikoden III): WoS can mess with Zero some, as does Hugo's better speed and evade. I don't think auto-crit attacks are ITE on the PC end (or maybe they just don't ignore flying?), and Zero doesn't OHKO turn 1 anyway...
Empoleon (Pokémon) vs Legretta (Tales of the Abyss): EDIT: Swords Dance Drill Peck. Well. Hmm. That's not the best buff damage, but it may be good enough, even hitting the wrong defence here. Searing Sorrow being fire creates real problems, though. RE-EDIT: Even buffed, Empoleon 3HKOs, which means he probably faces at least two Searing Sorrows, 1 if he can really monkey with his damage. That's too much, seeing as Searing Sorrow 2HKOs, and Legretta will do about half his HP in damage while he buffs.
Balthier (Final Fantasy Tactics: War of the Lions) vs Feena (Grandia): Balthier could equip robes? Dunno why I assumed he couldn't. (Idle, no vote obviously.)
Middle
Greg Russellburg (Wild ARMs 5) vs Wiegraf Folles (Final Fantasy Tactics): 2HKOs, isn't OHKOed.
Queen Bean (Mario and Luigi: Superstar Saga) vs Kimahri Ronso (Final Fantasy X): M&L boss who isn't Fawful = auto loss in any division besides Light.
Light
Sanaki (Fire Emblem: Radiant Dawn) vs Algus Sadalfas (Final Fantasy Tactics): Probably one-rounds or something.
Tony (Wild ARMs XF) vs Erk (Fire Emblem: The Blazing Sword): I think...
Rogue Tomato (Final Fantasy XII) vs Augst Henriksen (Wild ARMs 4): AWESOME.