I played MK Wii with a friend and I have to say... we really couldn't get the motion controls to work half the time. It's a great idea on paper to have special moves executed through movements, but I think the program has a difficult time deciphering between a half circle and a line. Maybe it was us...who knows, but it was mostly us waving our hands in the air trying to do special attacks. Plus, the D-pad is used for Kicking and Punching and it's not very comfortable to reach all the way up there.
Luckily, the Classic and the Gamecube controllers are compatible.
So in all: I think a fighting game made specifically for Wii could definitely work. Unfortunately in this case, the control scheme feels very "ported" and not natural.