From what I know - no. File in ~83% is composed with zlib chunk files (mostly textures). Rest of them looks like uncompressed files or some other type of data.
It's not encrypted, that's for sure. But composition is weird.
Try to find in this big file text or uncompress chunks with offzip and try to find text in uncompressed chunks.
The arslan quick bms script can extract fe:3h as it's the usual musou file structure. You just have to rename DATA0.bin/DATA1.bin to LINKDATA.IDX/LINKDATA.BIN. But be warned that there's no name table so it will be very difficult to figure out what file is what. https://zenhax.com/viewtopic.php?t=2191
Apparently you can unlock all the support conversations by editing your system savefile with a hex editor, thats all I know since the person who did it can't reveal it yet since they have a deal with a YouTuber that won't allow him to reveal it