Yes, any visa card can be used. China Bank International Credit Card can be used in China as long as it has the signs of UnionPay or VISA, MASTER, American Express, JCB, etc.
Yes Canadian bank cards can withdraw money at Hong Kong branch. Yes, you can get it from the ATM of Hongkong Bank in China. However, it seems that not all ATMs can take it, but there are some special ones.
Canada's UnionPay card can be used in China. It's easier to handle VISA and MasterCard.
Jiahua bank card can withdraw money in China. It is suggested that foreign bank cards should contact the issuing bank first to confirm that the global cash withdrawal business has been opened, and then withdraw money from large banks such as the five major domestic banks. If it is a credit card, you can withdraw money at the bank counter or any ATM machine with its logo. The withdrawal is RMB.