Would be a pain the arse if you needed to have the stem pressed in. It may also mess up the handling of the bike as they will most likely be a different length stanchion.
If its just for looks i personally wouldnt bother.
in theory you could put YZ forks (including brakes and wheels) on it providing they have the same yoke diameter, failing that you could swap out the whole 3-tree (yokes) fro, the YZ provided that the internal spindle is of the same diameter.