Since everybody here is refraining from mentioning the forum name, it's called the rom hacking and translations forum, found here :
https://gbatemp.net/forums/3ds-rom-hacking-translations-and-utilities.276/. People here will have more of a knowledge on translation. Also, saying changing text in a game is extremely broad. You could say you want to learn a language, but when I'm done you can't just go to France. Just like how you can't learn how to rom hack 1 game and do it to all of them. Each game has its own files and format, and very few games are exactly alike in file systems. What games are you thinking about?