This comic was posted in the K. Rool thread, but I felt it'd be better to address it here.
Defer to this post.
I never did get this logic.
"Why Corrin and not someone for Star Fox Zero or Zelda Wii U?"
Who from Zelda Wii U? Link and Zelda, the two major characters that are practically confirmed as soon as a new game is announced, are already in Smash.
Regardless of whether or not Ganon/Ganondorf is going to have a presence, he's in Smash too.
So, what, throw in some random side character literally no one knows about at this point in time to advertise the game? Brilliant idea!
And for Star Fox, no one would really "advertise" for it.
"What about Wolf", you ask? He's been in Smash already. He wouldn't be advertisement for Zero, he'd just be a returning fan favorite.
So unless you people want someone like Slippy or a character original to Zero, don't use it as a counter.
Now Inklings would be a good example.....
.....if their Mii Costumes and Trophy weren't literally already used to promote the game before it released.
In the case of Fire Emblem Fates, there has been no promotion in Smash until now, and the game has only been released in Japan thus far. If Corrin was included to promote the game, it's to promote the overseas release, which won't be until around Corrin's DLC release.