[Script] About translating a ROM Hack

Hello everyone, I'd wanted to ask you: how may I translate PKMN Blaze Black 2 / Volt White 2? Someone called "Moumph" translated Volt White to spanish - it's the original spanish version but with those little changes. So, I wonder if it's as easy as applying the patch to the ROM and then... changing the language (and then translating yourself the script)? I know nothing about ROM hacking, and since I haven't found BB/VW2 translated, I decided to do it myself. Could anyone help me?

Edit: I've started extracting .narc files from the ROM and then editing them with PPTXT. It's a little bit confusing but let's see what happens.

Edit2: I've translated the first Juniper lines but I realized I'd have to translate THE WHOLE game. Wouldn't it be easier if I could apply the .xdelta patch to a spanish ROM and then edit only the changes? (The problem is that the patch only works on the (U) version)

I'm sure that the patch it's just for the specified version, but you should try and see if it's possible.
If not, you'll have to translate the whole game, ask permission to the creator and maybe gather a team of people so you could create a patch for the game translation. Buena suerte!