They really dont even NEED time travel to have 2 Belmonts.
here's an idea. Sonia is the heir to vampire Killer, and Victor is still a Belmont who ran away from his destiny. He could be Sonia's brother or something. Or make him older and be her uncle. Thus he is still a Belmont, but he doesnt use a whip, and has his own play style. Evil arises and fate makes it so he has to face his destiny and aid Sonia.
I had the same idea. I would be interesting, having Victor Sonia's older brother, who was meant to inherit the VK, but chickened out of his duty, so Sonia stepped up and said, "Hey, if he's not going to do it, somebody DOES, so hand it over! I'll be happy to be this generation's ass kickin' Belmont warrior!!". Maybe toss in some tension regarding resentment. Victor might come back wanting to reclaim his birthright and Sonia will go, "No way! You snooze, you loose! Play second fiddle to ME, the REAL Belmont hero...er...HEROINE!!!!". That could be pretty damn good, actually. Konami, quit being a douche! DO IT!!

Not everyone is head over heels for Kojima's designs, I for one would be sickened by the idea I'd rather see a few other artists given a chance.The intro cinematic for resurrection looks pretty decent & what we are seeing is concept designs presumably fairly early so the finished game could still be quite nice without needing to be remade.
I only mentioned Ayami because I'm partial to her style, though ANYBODY would be better(even though I'd probably keep away from the LoS Middle-Earth artstyle, as well as the horrible Judgement DeathNote style). The artist who did Ooe, or even the ones who did CotM and the CV64 games(which are the most anime-like for being 3D). But really, I loath the general character art style of Resurrection. Some of those designs reek of "extreme 90s"(I'm guessing it started development somewhere in the LATE 90s, given it was cancelled in March 2000). That style is vomit inducing, IMO. I wasn't a fan of that type of style back when I was a teen during the 90s(even though some of my friends, at the time, ate that crap up like it was candy), I particularly don't think it's right for the CV series. It's the reason I liked the general art direction of the CV series during the 90s.