This is an okay thing to do, as long as your intentions are not to “save” them from their own people.
But I would expose them to their culture as much as possible growing up, and like, enroll them in a cultural school (Chinese school, Japanese school, etc)/take them to a community center for people of their culture or Asian people in general. I suffered a lot because I lacked this (I’m diaspora first generation Han Chinese and my parents were both raised in the USA even though Mom was born in HK when it was China).
I would also recommend raising them in an environment where they will be able to be around people like them – like not just Asian people, but Asian people of their ethnicity. So if they’re Han Chinese, find an area where a lot of Han Chinese people live.
(Do any transracial adoptee followers wanna chime in?)
Also, beyond the “don’t play white savior”, “don’t fetichize them”, and all the stuff about intentions- be careful about how and where you adopt! Be aware that sometimes children are called “orphans” even though they still have family alive. Be aware that child trafficking exists, that there have been adoption agencies who coerce and pay women to give up their children, that the ‘fashion’ of adopting children abroad has been said to create a ‘market’ for children of color - so to parents who want to go this route - do your research!
Adopting Asian children isn’t in and of itself a bad thing, but it’s not hard to unintentionally play into really harmful dynamics, so being really careful about that is essential.