D1 may have accidentally leaked something from Nintendo being playable at Apex

[PixelPerfect]

https://www.youtube.com/watch?v=R27dVfBeiUE

 

So, yesterday at Paragon, a large Smash Bros. tournament, one of the commentators named D1 began talking about Apex and that something is going to be playable there then immediately goes back on his words as if he wasn't supposed to reveal it.  Since Nintendo is sponsoring the Smash Bros. brackets at Apex this year, what could this be?  Some speculation has led to some rumors such as a possible Splatoon played in a tournament like fashion, a possible Pokken Tournament demo being playable or heck even a first look at Mewtwo in Smash 4.

 

What do you guys think?