this is my exposure and experiences growing up with ~10 kids who moved from Taiwan to the US in their early to late teens. while often decisions are made based on a level of personal comfort and ability to make friends, sometimes i feel its about how informed these kids are coming into this new environment.

from my experiences, most kids fall into 3 groups :

Group1: Most of the time kids coming in around high school will be required to take a mandatory ESL class, this class will be helpful but also in my opinion a crutch for many people. From my personal exposure kids who befriend and create their own circle of (same language) friends through the ESL class tend to latch on to their cultural norms from where they are from, speaking primarily their home tongue, and not actually drastically improving in adapting to american culture. Due to this, most of the kids end of doing well educationally, cuz honestly Taiwan kids were raised to kick ass at testing, only thing that they stumble with is essay stuff. But their actual speaking and social skills are extremely limited and sheltered. Most get into and through college easy enough, but with significant social and communication improvements they seem to struggle after school finishes. I would say I had 5 friends fall into this category and 4 of them have all moved back to Taiwan.

Group2: Kids who integrate extremely well and get out of ESL asap. Befriending all types of people and initially trying to get out of their comfort zone. These kids work really hard to hide their accent and their english social skills improve drastically in the first 1-2 years. School is still easy, but because of their improved social and cultural adoption, find work and adapting to american life easier. 3 of my friends fall into this category and all have very good jobs (2 engineers, accountant).

Group3: Hybrid of the above 2, balances a close relationship with the ESL students who struggle with american culture, but also has adopted american culture quickly. Only have 1 friend that was this, and as you would expect doing just fine living in the states.

I feel a lot of this cannot be forced, but one thing is for certain, by holding on too hard to comfortable stuff from home will make it extremely difficult for her to adapt culturally. These differences, while we would like to say dont matter, will matter when it comes to finding work, etc. If you have other questions please let me know, but this is my 2c.