Pochahantas 2 and MK3 (slightly re-skinned port of MK2) aren't that bad, in MY opinion. Pochahantas 2 is much better than the sluggish, confusing, and story-removed (I mean with text and cutscenes) Game Boy version. I also like Master Fighter VI, because it has all the fighters from the arcade version. And, of course, Rocman X (NES, not GB)!
I didn't know there was a GBC version of Street Heroes! Also, there ARE some fighting games for the NES that aren't pirates. For example: Urban Champion!