CUE sheets should just work automatically. If it isn't working there might be something wrong with the one you're using.
Is it an external CUE file, or saved as a tag in the FLAC file?
MusicBee supports ISO characters, but they also need to be present in the font you're using.
If those extended characters aren't present MusicBee can't help with that.
However, it does look like you're using a standard Windows font so it might be something else.
Screenshots of the tag values might help to rule out some other possibilities.
Bee excellent to each other...