Bootleg = remix using the raw song, no stems. Some mashups are called bootlegs.
Flip = basically a remix or a bootleg that changes the vibe of the song completely.
VIP = variation in production. usually means that the original producer wrote the original song in a different way, like an artist remixing their own song.
Edit = minor change to the song, usually with the drop/tempo/something that changes the song, but not enough to re-mix it.
Rework/re-edit = a flip or remix usually of a song that’s already remixed or edited.
Mashup = mashing two or more songs.