- Sound Editor 2018 (the "installer" version)
2. Dumping the Stream.pckDownload NXDumpTool from here and put it on your SD card.
Run it. If your copy of Sword/Shield is on a game card, select "Dump gamecard content". Else, select "Dump installed SD card / eMMC content".
Then select RomFS options > Browse RomFS section
The Stream.pck is located in bin/sound/NX64/wwise/bank.
If you get an error message saying that prod.keys cannot be found, run Lockpick_RCM, then try again. Then (obviously) copy the Stream.pck to your computer.
3. Converting and injectingIf you run Sound Editor 2018 for the first time, you will be prompted to install Wwise. Click OK and it will run the Launcher installer. Then you need to login or register with your Wwise account. Click on install in the Wwise Launcher. After everything is done, return to Sound Editor 2018 and select Settings > Settings.
In there, set the main Wwise directory to the folder you installed Wwise into. (Typically Program Files\Audiokinetic\Wwise 2017.1.2.6361) and set the WEM-Export directory to the folder you want to save your files in. Now you're done with the setup. Click Save.
Select Tools > Sound Converter. Click the button next to Select sounds and select your .mp3 file. (it must be an mp3 file). Then click Convert and wait for it to finish.
4. Now the actual injectingPress File > Open and select your Stream.pck file. I typically sort by size so the music files are at the top (Press on Size).
Right-click on an entry and hit Play to hear the sound file. If this is the sound you want to replace, Right-click on it and hit Import. Then select the converted .wem file that is in your export directory you selected earlier. Wait until it says "File data injected" in the bottom left.
5. You're done!You now just need to copy your modified Stream.pck to your cfw's LayeredFS directory (contents or titles).
Example with Atmosphere 0.10.1 and Pokémon Sword:
Note: Since this tool is meant for WWE 2k18, the injected music is not perfect, but it works.
(Sorry for bad formatting or other stuff, this is my first tutorial.)