EDITED: Oops, I'm not supposed to post any links until I have more posts, but if you search for Petschko you should find a Gitlab repository for a Java RPG Maker MV decrypter. That one worked for me.
The same creator also has a web version, but the Java version is much nicer for just pointing it at the directory and decrypting all the files that way. You'll have to copy the output back into your actual game folder afterwards. (You may also want to make a backup, just in case.)
It says one needs a decrypter key in order to decrypt the files. Any way around this?
EDIT: For those who couldn't decrypt like myself, take a look at
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You essentially need to analyze one of the game's encrypted files on
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(I just use any of the .png_ files in the www/img/pictures folder).
The website is only used to get the encryption key. You then take that encryption key to
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Start the tool using start.bat (on windows) and then select the folder containing your game.
"Set Encryption Key" and then "Decrypt all. (both within the drop-down menus at the top of the tool)"
The decrypted files will then end up in the output folder of the decrypter. Copy/overwrite these files into the game folder.
Then add the translation files to the game and you're done.
You probably have to have
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in order to use the tool.