1. Find a decrypted CIA of Sun/Moon.
2. Download the latest version of
Asia81's PackHack and run SetupUS.exe to install the PackHack.
3. Move that decrypted CIA of Sun/Moon into the same folder as HackingToolkit3DS.exe.
4. Open HackingToolkit3DS.exe, type ME, and when it asks you if you want to decompress code.bin,
HIT Y for yes. This is important.
5. Remember, this game is huge so it'll take some time to finish.
6. After it's done, you find a folder called <name of decrypted CIA>.cia_Unpacked. Go inside that folder, go inside of the ExtractedExeFS folder, and find your code.bin.
7. Make a folder on your desktop named SaltySD and place your code.bin file inside of that folder.
8. Follow the instructions on
this post to patch your code.bin with SaltySD.
9. Once you have patched the code.bin file, rename it to the title ID of Sun/Moon.
10. Go to your luma folder and make a folder called code_sections in that folder. In the code_sections folder, place your .bin file.
11. Place your .bcstm files with the exact name of the file that they are replacing inside of saltysd/SunMoon/data/sound. The saltysd folder should be on the root of your SD card.
12. Open your luma settings and make sure that Enable region/language emu. and ext. .code is enabled.
13. Launch Sun/Moon to see if the changes have been made.
Tips:
-You can't just place any music file inside of the data/sound folder. Once you have extracted the contents of your decrypted CIA, go into the <name of decrypted CIA>.cia_Unpacked folder, go inside of the ExtractedRomFS folder, open the data folder, and open the sound folder. Inside of the sound folder is all of the sounds inside of the game. You'll want the .bcstm file you find online to match the EXACT name of the .bcstm file inside of the data/sound folder. I recommend finding the BCSTM to WAV Converter to be able to listen to what each file is.