Well throwing an already existing Wii U stage into the 3DS version woudn't take any development time at all.
Literally all they would have to do is reduce the vertices on models and lower the textures and maybe adjust the size for the 3DS standards. For something like Pac-Land, they wouldn't even need to do as much that.
The reverse isn't true though. Adding 3DS stages to Wii U would take time if they want to update everything for the Wii U (though honestly, still not that much.
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I was just thinking about cancelling this today but I guess it's too late now.
Time to become a weeb dragon/piece of corn.
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Oh snap
Should be noted that this is the exact same time as the Zelda Treehouse stream, so it could just be a mistake/stretched use of the "Nintendo Direct" term.
Unless the stream starts with a Direct or something.