Fast-forwarding this thread to date, I find that, using an Apple Watch S7 A2478 with 8.6, in the case of fixing an non-purchased album that's no longer on the music store, if you grab a plID from some random album (one you know that you'll never purchase), then playing to an iPhone remotely works, but no artwork displays in the watch music list, even if you've embedded it in the file. It's odd, because while it's playing, a blurred version of the embedded artwork does seem to show behind the controls. Getting a plID with the correct artwork does show that artwork in the list.
Even so, it's all quite a chore. Some better automation is needed.
But I wish Apple would just fix this. It seems wrong that it works if you get a Music subscription - but I won't do that again - I get the wrong recordings of my best classical music.
Even so, it's all quite a chore. Some better automation is needed.
But I wish Apple would just fix this. It seems wrong that it works if you get a Music subscription - but I won't do that again - I get the wrong recordings of my best classical music.