Remote Watch Pass subscription through mobile app

https://www.plex.tv/blog/important-2025-plex-updates/#what-if-ive-already-paid-the-one-time-mobile-app-activation-fee

I use Android and can’t figure out how to do this, is it to early?

Yes. That policy goes into affect with the new player which isn’t out yet, it’s still in preview at this time.