Just like the title goes. No one wants GCBD.
Every article I found on the internet suggests that there are no way but to backup everything yourself, then create a new account and select region besides China Mainland, try to get all of those backup data back to your new account. However it is not only tedious but also poses a risk of losing part of the data (e.g. Live Photo, Device Backups).
Is there really no way to transfer it more elegantly?