Hi everyone, I may have found a solution or workaround to this problem. But will need your help testing to see if it is stable.
I found that if I play music directly from the iPhone, Apple Watch will display the album cover art. But if I play music through my Air Pods Pro 2, no album cover art is displayed. So I did the following:
1. Disconnect Air Pods Pro 2 from Bluetooth.
2. Turn off Bluetooth.
3. Restart the iPhone.
4. Turn Bluetooth back on.
5. Pair Air Pods Pro 2.
6. Play some music, check to see if the cover art is displayed on Apple Watch.
7. Listen to music through Air Pods Pro 2.
I've taken out the Air Pods Pro 2 for about an hour, then reinserted, played some music and album cover art is still displayed on the Apple Watch.
Look forward to reading your replies and results.