Hacking ErrDisp for Cartridge

[iHaveNoideaWhatimDoing]

Has anyone had success getting Fire Emblem Warriors on a cartridge working on a JP N3dsLL with CFW? I have successfully changed my region to USA following the guide on hacks.guide.
Everything is in English and everything else works normally.
As a precautionary I have left these settings in place after changing my region:

• Game Patching is enabled in Rosalina's boot menu
• a locale.txt containing USA EN is loaded in luma\titles\000400000F70CC00
• a 000400000F70CC00.txt containing USA EN is loaded in luma\locales
• My SD card is healthy and several other games have worked even before the region change with these adjustments, I've been enjoying Bravely Default and Majora's Mask.

I'm receiving this error code:
Error type: card removed
The card was removed.
-------------------------------------
Error type: generic
Process ID: 63 (also sometimes 59)
Process name: Troop
Process title ID: 0x000400000f70cc00
Address: 0x0019ba8c
Error code: 0xc8804471

Any help is appreciated, thanks!


P.S. A fresh cia install of Universal Updater is still showing up in Japanese for some reason.....

EDIT: It seems for some reason existing data localized as JP carried over for the transfer. Going into individual title settings let me change to English. Funny enough the Language settings in Fire Emblem Warriors was selected in English as Japanese, but changing it to French before reverting to English fixed that.

 

[iHaveNoideaWhatimDoing]

ALRIGHT. I got it finally to work after installing the update from a .cia. HOWEVER. Even though my system now has the USA/En Region and language settings, and it's firmware shows as 11.14.0-46U in System Settings, AND the game cartridge is USA, it's STILL showing up in Japanese. What the heck?