@TANTRIC please read this

Is It Possible of Adding a Cover Mod on The snesxGx, vbagx and FCE Ultra GX??? is yes can you do it?? i would donate for it to happen :)

There is a cover mod for SNES9xGX, and it's listed somewhere near the bottom of it's Wiibrew page entry. However, the mod is based on an older version of SNES9xGX, so it's your call...

I dunno about the other two emulators, and while I support your idea, I don't think that he'll do it even if you pay him. It would require rewriting several parts of his emulators to get it work, and as far as I know, Tantric is only giving periodical maintenance to these ports, like updating to the latest revision and other very minor issues.