MusicBee scrobbles its unique Display Artist tag
to Last.fm, not the <Artists> tag.
This is better behavior than Spotify, as it allows all artists to be properly tagged within the file, but enables the user to specify exactly how they wish to scrobble the artist to Last.fm.
I'm unfamiliar with the bracketed behavior you mentioned, but with Virtual Tags
it is possible to display your tags however you wish.
With a Virtual Tag, the number of columns I use ends up simple:
Track Number | Display Artist | LABEL | Time | Play Count
I use all uppercase letters to reference Virtual Tags. In particular with the LABEL tag, I've spent an unhealthy amount of time adding and perfecting all of the information it contains, but you should find it very easy to toss <Artist> feat. <Artists: Guest>
or whatever into yours and display the Virtual Tag in play of the Display Artist tag where you wish.