I was paranoid in case Blizzard sees that I've been playing+botting the account mostly on my desktop in the US and they would do something to the account if I started playing+botting in China. Anyone have any experience with this?
Your account will be locked and you'll just have to unlock it. You'll be fine but you could save yourself the trouble of that and setup a botting schedule with HBRelog and setup your computer to sleep or shutdown on a timer and wake or turn on at a certain time. You could also use TeamViewer or other remote management software to maintain your bot from china.
Blizzard usually investigate accounts after players reports. Relocating from US to China, and accessing the account from there on a permanent basis should trigger only a one-time locking. as lilsavalex already mentioned, but IF GM investigate it for any reason (like player reports lol!), that China IP would ring them a bell that the account have been hacked and used from unauthorized person, so you could save your ass if get perma-banned later. But only if you appeal from USA based IP (since your battle.net country is USA)