I am planning to move back to Taiwan and bring my soon to be 14 year old daughter with me, she can speak Mandarin averagely, but can barely read/write any Chinese. I am looking into International Schools in Taipei as my husband lives there, any recommendations for her education?
Does your daughter hold a non-Taiwanese passport? That is the first step to getting into an international school.
Yes, we both hold a New Zealand and Taiwan passport.
Your options are wide open then 
.
Top-tier international schools in Taipei include Taipei American School and Taipei European School. If you are religious, you may like to check Morrison Academy or Kuei Shan school. Kuei Shan has IB Middle Years Programme (MYP) for grades 6 - 10, as well as Diploma Programme for grades 11-12.
Sounds good How long are waiting lines? Is it possible for her to get in by August (new school year)?
Not sure about that… you’d best contact each school’s enrollment centre to ask about waiting lists, etc.
Is your goal for your daughter to continue her studies in English at the same level/standard as in her current school, or to learn Chinese and adapt to the local system?
If it’s the latter, one of the local private bilingual schools might be a better choice. There are a few options and you would probably choose the one closest to your home.