As you see here, it states on Nintendo’s E3 page that the game will be played on Nintendo Switch. It also mentions For Fun and For Glory, which are online modes in Smash for Wii U.
Because of this, I think it’s highly likely that Smash Switch will be a port. There is no reason for those Wii U modes to have been referenced otherwise. Why bring something up from a past game if the game being advertised isn’t a port of said past game?
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