Add the Trophie Stand from brawl/melee (i can't recall which part it was) in their "adventure mode" as an item. It can turn the target into a non-collectable trophie, stunning them for 4 seconds, or it could just have a mild strong impact effect that will launch the target. yeah, it might sound over powered, but the animations to actually throwing the item takes like 1.5 - 2 seconds long.