I think u dont put in too much hope.
If it is supported, it should be supported long ago like the op12.
At least that is what i observed so far.
If you want to take the risk by all means go ahead bro. We have already shared a dozen times liao, and even one shared here that his china set with global rom lost cellular connection after an OTA update.
Honestly speaking, it is a ticking time bomb for me. And the cost between china sets and local sets are not too far off in pricing this time round. And oneplus can just do something to break anything in a software update in the future, by then, maybe those shopee/lazada sellers wont entertain u already as u have already used the phone for some time.
Hopefully dont see you come forum asking for help and kpkb lor if you decide to hoot china set with global rom