It will be a Nintendo IP unless it go's on to sell like 3 mil+ on Switch then Sega might be like okay MINE MINE and make 4 multi plat.
But yea, otherwise it's staying Nintendo only as Sega doesn't think it's worth it to fund the games.
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Donkey Kong Country Tropical Freeze, but I'm more confidant in that being ported then I am Mario Maker. Smash is showing up at some point almost guaranteed. It's like the worst kept secret from Nintendo ever and obvious. Probably Jan direct.
Also Splatoon 1 maintains an active online community and probably the reason I keep my Wii U hooked up. Splatoon 2 is nice, but some things are better in Splatoon 1 to go back to every now and then.
Super Mario 3D World, NSMBU/NSLU(actually the only good game in the NSMB franchise IMO), Pikmin 3 are also still good Wii U games that I doubt will be ported.