A lot of expats will try incredibly hard to prove that they are "one of the good ones" to try and fit in with the racist white people in their new country, by constantly badmouthing their home country and talking about how "superior" white culture is. They get empty, shallow relationships with people where they spend their entire time licking boot and either being mocked or fetishised.

(EDIT: this person is NOT from Taiwan), so they probably don't even know that they're spreading misinformation, they probably think they're being genuine. Not sure there's anything you can do about this though. Sure, they'll spread misinformation, but it's only stuff the gullible racist white folks around her already belief (or want to believe). You confronting her or trying to disprove her claims will be ignored, because she's Chinese and you aren't, therefore she knows more in every circumstance automatically, as long as she agrees with the western status quo of course.

Just...try not to be bothered by it. Maybe speak to her in private, try to understand why she says the things she does, try to understand her as a person, maybe even make friends with her, she might not be as horrible as you initially think. You're not going to change any minds trying to "debunk" everything she says, and you're only going to make enemies that way. You need to be friendly and sincere, you don't need to hide your opinions, but you don't need to shove them in people's faces either. People aren't going to change their mind just because they were "proven wrong." People just double down on bad ideas if they're challenged on them like that. It needs to be a slow, steady, educational process, teaching people how to understand sources and judge claims and challenge their preconceived notions.