I'm a fan of both Pokemon and 2D fighters, so I think you can imagine how I feel about this It looks like the Guilty Gear engine...I wonder if that's what they used? Either way it looks pretty good!
You could do this in M.U.G.E.N. But I don't think this is that, you should look it up if your a diehard.(would normally link to it, but i don't know what is the actual official webpage)