how to edit just one eye on a character's texture

[playermode]

I need to know if its even possible to edit just one eye on a character texture. im trying to make an Old Snake with his Solid Eye patch...and when i checked it in game...i can still see his eye and both of them have this weird white trim or something. i figured it could be done cuz i seen a few Metaknights with just one eye. Well if the latter is true, can anyone tell me how can it be done?

 

[codfish92]

may not be possible with snake cuz his face is mirrored, while meta knights is not.

 

[shadowtroop]

Actually, the one eye thing on metas is a glitch that prevents the face from mirroring. There is no way otherwise.