Yup, there are three options under "bluetooth metadata" in the settings menu, and I've tried toggling all three options, and no artist/track info has shown up on my car's HUD. The options are:
1) Metachanged Intent
2) CyanogenMod Metachanged Intent
3) Send Album - Artist with Metachanged Intent
None of these have solved the problem, unfortunately. I have a feeling that it has less to do with Poweramp , and more to do with the actual bluetooth AVRCP being sent from the galaxy S8, but if there's a chance it can be something that Poweramp can fix on its end, that