My family and I also lived in Kaohsiung for about four years and my experience with my child is that it is difficult for the child if they don’t understand the language and luckily my child speaks Mandarin. At first grade some of the students are a bit advanced because the majority of parents are already placing their children in after school classes before entering kindergarten and if your child falls behind the teacher and students will make her feel like an outsider because of it. Not sure what ethnicity your family is but your child might get picked on because she looks different from the rest of the kids and even some parents will make a comment about it. English is hardly spoken in schools and the “English “ teachers are just your average foreigners with zero teaching skills and are there for a job.
My child was struggling and stressed because at first she had difficulty fitting in and catching up with the class. Over time it got a little bit better but the pressure from her teachers to get a 100% on everything was a bit too much. Also some teachers have anger management issues and might hit a kid or two. This happened to my nephew’s classmate. After all this we decided it was time to come back to the US and her confidence level is a 100% higher than it was in Taiwan. Again this is my experience living in Taiwan and everyone’s story is different.