On one video during the battle of Xezat's fleet, I saw an image where Gilamesh and Enkidu were playable sprites while the main party were the bosses. Does anyone know what I am referring to?
I remember that pic, but not a video of it, which video are you referencing? Anyways as far as I know it is just one of the many Japanese meme screenshot edits I thought. Maybe it's a small hack, though, but I highly doubt they did a full sheet of them, and if so, I've never seen them floating around anywhere.
EDIT: this pic, right?:
https://imgur.com/a/oz96ZDj
It's just some pixel art, it's not a hack.
Yes that is what I was looking for. Thank you. I remember seeing the image on a youtube video of FF boss themes.