You can rename spells via macros but it will not change their effect or how they are labeled in your battle log.

/echo is what is used in a macro to make it so you get the text instead of the party. Great for RP who do not want to annoy non RP

You cannot change eyepatch sides, you can look to see if there is one that covers the other eye, but that would be the only solution. You can use the Eorzean database and do keyword searches or use the "try on" function in game to go through and find one if nothing else.

https://na.finalfantasyxiv.com/lodestone/playguide/db/