Okay, I get what he wants to do, but the gaping flaw is this:
ESF is defined by it's gameplay, not by it's content. Even using the sprites, models textures, what have you, even disregarding the fact that the model's rigging would likely need to be remade, recreating ESF's gameplay is where a single person is likely to fail. This game is several years old, and has been worked on and built on by MANY people. And while I think ESF is far from perfect, it's pretty damn impressive.
But while I know the modellers for ESF are excellent, and have really done a fantastic job stretching Half Life's engine to it's graphical limits and then some, I think it'd be a waste to go through all this effort and use models and graphics that were designed for real-time handling by a game that could likely be run comfortably by the original Playstation. I mean, you're porting it all to a 360. Make some use of that next-gen magic! I know that aside from ZEQ2 and DBZHOOD that there aren't many choices for quality DBZ models unless you make one yourself, but Hell, go that extra mile!