I've made 5 games on App Store in Chinese area from 2016. All of these games were localized with English, Chinese, German, French, Spain and the other languages.
In your case, I suggest only give me the English version text file with all strings in the app, and I can download the apps from App Store with USA account. And I'll help you to fill all the data needed in App Store in Chinese area.
If there is some words in preview images, those need translate too. I can modify these images in PS, with suitable Chinese fonts. As you know, some of app in Chinese use bad fonts and that's very ugly to the Chinese persons.
If you have interesting with my suggestion, please contact me with email. If I start working, I can also discuss with you by Skype, Wechat or the other IM apps. I'll submit process with you every day, and submit time will follow your work time and timezone.