R.O.B: Might work. Give it Gyro Ball. If you've played Brawl, you'll know why.
IC: Not too sure, they're two separate beings, it's not like Doduo/Dodrio, or Dugtrio, or Magneton... they're all one pokemon (though some could argue about Magneton). But the Ice Climbers are two different humans... Though they made in work in SSB, so it might work here... IDK.
G&W: Would be unique, that's for sure. Give it a Judge attack, similar to Melee and Brawl, where it's affect depends on the number generated.
Sukapon: I don't even know who this is, so I'm definitely not voting for Sukapon.
My vote is for Mr. Game & Watch.
Official Team Miror Infinity Admin!!! Shadow Pokemon: Pikagod!