Your questions about SoFi Hong Kong are answered here

Fractional Shares orders are not executed real-time. They are executed during the “Order Dealing Period”. All Fractional Share Orders for a stock are executed in batch once per day so there might be an impact on the execution price of your order. This will help minimize our cost to offer fractional trading services and in return offer $0 commission fees. The execution price will be within 20% market price deviation as indicated in the “Your Fractional Order Arrangement” notifications. If you do not accept the order execution and allocation arrangement, you can cancel your order during the Cooling Period.