Your questions about SoFi Hong Kong are answered here

The SoFi Hong Kong App is our mobile stock trading app. It is available on the App Store or Google Play. You can trade over 15,000 US, Hong Kong and China H shares and exchange traded funds. You can hold your account in USD, HKD or RMB. SoFi Hong Kong is built on the latest technology and infrastructure to ensure your trades are fast and stable.