We ALL KNOW that Goku got robbed in that bullshit Smash Bros. poll from last year. But that's OK. Modders have made everything right again. What you're looking at above is a mod for Smash Bros 4, as showcased by Super Mega Buster 123 Win64 Gigabyte. The mod was created by KevintheH, and it replaces Ryu's model with Goku textures, as you can see below:
It is not a purely cosmetic modification, either. Goku actually sounds like, well, Goku — down to the Kamehamehas. That said, the mod doesn't appear to be done, as the video calls this a beta. Still, it's awesome that modders are figuring any of this out in the first place.
Goku's actually not the only character that has been added to Smash 4. Modders have also been busy tweaking characters like Captain Falcon and Samus into replicas of Captain America and Iron Man, amazingly enough.