Did you knew that dolphin emulates WFS? And that it emulates the Wiiu version?!? Seems that a particular wii game uses an USB drive to store contents and patches, and it's handled using backported IOSU routines. Emu's devs reversed most of it, maybe it can be useful for your lib ;)
https://it.dolphin-emu.org/blog/2017/08/23/emulating-dqx-online/
Take a look at the end of the article.
https://it.dolphin-emu.org/blog/2017/08/23/emulating-dqx-online/
Take a look at the end of the article.