No.
Yes.
No.
Support, if you own Hong Kong stocks or US stocks assets and activate the function of Unified Buying power, then you can directly buy A-shares stocks.
the External Fees charging information can be found on the website of the Hong Kong Exchanges and Clearing LIimited("HKEX"):
Settlement and settlement fees
The trading of SZSE Securities which are listed on the ChiNext market and SSE Securities which are listed on the STAR market will be only limited to institutional professional investors.
Institutional professional investors refer to companies that manage investment schemes, such as banks, insurance companies and brokerages.