Godlike:
Zophar (Lunar:EBC) vs Deamoned (BoF5) - Zophar. Having at least two eyes allows him to win here. Deamoned's lack of depth perception prevents him from moving around enough to avoid Zophar's attacks, meaning he can't move up properly.
Mewtwo (PKMN) vs Zenon (Disgaea 2) - Zenon. Can move around the battle field. Even though he's part fish, he resists fire, ice, wind...which makes him...well, hard to quantify in Pokemon terms, but certainly not weak to Psychic. Mewtwo wants RBY form, but there's no range on that form's attacks, and he can't (or she can't) move in the battle, so Zenon can stand at a distance and fire off whatever he wants.
Citan Uzuki (XG) vs Erikia (FE8) - Citan. All he has to do is ask her if she'll give him her weapons. She will, then she won't be able to fight due to lacking weapons, and she can't even use her breasts to fight back since they're so small. Also, since the rules say it's only the person fighting, I don't let her use her horse, which means she's either limited to unpromoted form, or loses stats (most likely speed and possibly defense, which hurts like hell here).
Tibarn (FE9) vs Yuri Volte Hyuga (SHs) - Yuri. In the world of birds, the bigger wings tend to mean great power. Dark Seraphim has much, much larger wings that Tibarn. Tibarn is out-manned and forfeits.
Heavy:
Zero (MMXCM) vs Reno (FF7) - Zero. Both have equally short names, but Zero has the advantage of using a sword. And a gun. Reno has lost to a SCC with a person using just a gun and just a sword. Since Zero can use both, I don't see how Reno has a chance here.
Jerin (Lufia 1) vs Mithos Yggdrasil (ToS) - Mithos. Much easier for him to strike her at her weakest - her innate feminine misgivings. Jerin as an elf is androgynous mostly - the problem is that the feminine desire to be a woman overrides that. Mithos looks much prettier in a dress, and once Jerin sees that, she'll go home and eat ice cream and get fat, because she can't stand being so unloved and confused for a man. The female mentality comes first, and that's her weakness here.
Daos (Lufias) vs Serge (CC) - Daos. Look at how fucking huge he is in battle. Seriously, he also has gigantic armour-plated cape-mail! Serge needs loads of stuff to take down the Time Devourer, which is about the same size. And that thing didn't have armour. Serge's weapon doesn't even touch Daos' divine skin, meaning he never takes damage. Meanwhile, Serge wears fisherman's clothes. Those protect from nothing.
Asellus (Saga) vs Angelo (DQ8) - Angelo. Asellus is a woman, but canon lesbian? Ok, assuming she is, Angelo is too hot - he can still woo her slightly, and I was under the impression she was more bisexual. As long as Angelo use protection (and I'm certain he has the spells for it), he's fine here in the dominating position.
Middle:
Lich (FF1) vs Flay Gunnar (MK) - Flay. 64-bit vs. 8-bit. This is no contest at all. Lich can't even see him due to being colour-blinded to such a small spectrum.
Beatrice (WA3) vs Shinjiro Aragaki (P3) - Beatrice. Shinjiro has a problem with recurring nightmares secondary to the disaster. Beatrice will simply get in his head and cause his persona to go out of control. Or simply modulate his memories so that he thinks she looks like the mother, driving him into a psychotic rage that causes his persona to destroy him.
Roxis Rosencrantz (MK) vs Gijimu (S2) - Roxis. Gijimu < Freed Y, by the sole fact that Freed gets laid. Guess why Freed gets laid? He has glasses. Guess what Roxis has that Gijimu has not? Glasses. They go out for a night on the town, and Roxis gets all the ass he wants, leaving Gijimu at home with a moist towel.
Nash Rumack (Lunar:SSSC) vs Slade (SF2) - Nash. Mithril conducts electricity just fine, thank you. Stupid rat, bringing metal to an electrical fight.
Light:
Kahn Marley (S2) vs Garet (GS) - Kahn. One of the issues with GS is that the characters are not used to voices, particularly loud ones. The game is rather soft. Kahn meanwhile has magical yelling and screaming. Once Garet is deafened by that, he can't ask any more annoying questions, meaning he's out of a job, homeless on the street giving handjobs for crack.
Duessel (FE8) vs Frank Goldfinger (SH3) - Frank. Since bowling balls don't exist in the FE world, Duessel will not be prepared for it. He'll walk his horse over it, and it will trip and fall down, giving him a concussion.
Mia Ausa (Lunar:SSSC) vs Zell Dincht (FF8) - Zell. Punching > slapping, and Zell can punch Gods - Mia only slaps Nash. Zell also beats the shit out of women (Adel, Edea, Fujin, etc.), so no hitting girls problems here.
Skelly (CC) vs Locke Cole (FF6) - Locke. Steals Skelly's pants. This might not be something problematic in a normal situation, but this will expose the fact that Skelly has the pubic bone structure of woman, which no one knew about. Public humiliation is not something gay undead clowns enjoy.
Do yourself a favour and try not to take me seriously >_>