You have haxchi, so I'll assume you can run it and get sig/region/iosuhax patching going.
Get
Fix94's ftpiiu_everywhere and put it on your SD card in /wiiu/apps/fpiiu-cbhc.
Run that app from homebrew launcher.
Connect to the address it shows using an FTP client (like filezilla or WinSCP) on the PC.
Navigate to /storage_mlc/usr/title/00050000/101c9300/content and start poking around. If you've installed to USB, it would be under storage_usb. The files might also be under 0005000e/101c9300 (the update directory)
So! I've been having a look inside of my E-Shop copy of the game, and I've found a bunch of folders inside, all in English. The only reference I can find to any form of "writing" per se, is "FONT", which is Japanese.
Replacing Font however for another font style won't change the in-game text to comprehensible English words. If anything, it'll try and display Japanese with English fillers and come out all garbled, if it even works.
I can't find anything else that alludes to it being actual subtitles or in-game dialogue. Voices I've found, but nothing else :/
Do you have a PAL or NA copy of the game that you can check to find exactly what I'm looking for?
Thanks again!
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I've found a file inside of "system" called "regionlangmask.txt
It's in Japanese, and I've changed JPjp to EUen and changed JP to EN.
This is in the original game dir, not the update dir.
Inside of the system folder in the update dir, there's an equivalent RegionLangMask.txt, but I can't download or edit it in Filezilla. It says Critical File Transfer Error. Something to do with permissions I believe, but I can't figure a way around it.