Your questions about SoFi Hong Kong are answered here

When you do not have specific currency to settle a transaction, SoFi Hong Kong will conduct FX conversion if you have any other currency available. Besides, you can instruct a FX conversion in SoFi Hong Kong App anytime. FX conversion will be processed on business days (Monday to Friday, exclude Hong Kong public holidays). FX instructions that is placed before the cut-off time of 11:00 HKT will be completed in the afternoon on the same day. Instruction received after the cut-off time will be handled on the next business day. Please note that the rate displayed in SoFi Hong Kong App is an indicative rate only, the actual rate of conversion will be different.