Maybe it's just a relic of me holding out for the Google Plus migration so long but my youtube account is a "brand account" which is definitely a thing I can transfer to another google account (indeed there were a few youtubers who got famously scammed last summer into doing this). Maybe yours is set up similarly?
Android apps will be a pain. I have apps that are no longer sold, or am grandfathered on a premium 1 time purchase for stuff that is now subscription based, etc.