I’ve used it for a while now. I will still probably use it on the desktop but for my phone/car I switched to Symfonium because of the stupid download restrictions of Plexamp. I like Symfonium well enough and it will also pull from Jellyfin if I ever fully get rid of Plex.
https://clonehero.net/ The best I have seen is Clone Hero. I had a good time with it in Windows with drums a few years ago. They are super slow on development though. No characters. No venues that I know of. But there are many songs out there. And it seems to work pretty well. Even did multiplayer over the internet.
They have moved around the song database since I last played but looks like it’s here now. https://rhythmverse.co/