This one replaces link's sprite, and changes the color pallet of the world a bit to look more like Equestria. He also swapped some of the text out, though this game was never very text heavy to begin with!
I'm curious... Would you guys be up for a sprite swapping competition? I honestly know very little about this, so I'm not too knowledgeable about the difficulty level.
I'm pretty sure ponies in any game is an improvement. (aside from Mortal Kombat, unless they really are made out of fluffy rebuild able marshmallow.)
Anyway, you can find the links in the youtube video description!