You can not open an account with a Chinese Bank in China from the UK, because they need your presence here to sign documents, copy your passport and visa, give a local address and phone number, set your account PIN number, etc.

But once you arrive here, it is maybe not quite one hour to do so.  I did mine with Bank of China, and I had opened one with their branch in New York prior to coming, but when I arrived here could not use it at a local bank.

Chinese banks are fragmented to the extreme.  A Bank of China branch in Jiangsu province can't communicate with a Bank of China in another province.  Therefore, you must wait until you get to your destination before opening an account.  This is one of the many surprises you will find at banks in China.  In fact, you may quickly find that banks are one of your least favorite destinations in China.  I don't go there unless it is absolutely necessary.  I still use my American bank for all my financial needs and it is well worth the extra cost.  You will understand after your first visit to a Chinese bank.

To open a bank account in China you must be in China because they will need your passport. Try to go to a big bank and with a large presence/branch because you might find that they will have someone in their 'international department' who can speak English reasonably well. That will make it very easy for you to fulfill your banking needs. Also, some American [do not know about UK banks] have partnerships, i.e partially owned by the American bank, then it is very easy to do your banking. You can even use your American ATM card in the Chinese bank and withdraw money from your account.

You still can apply for an account at the bank and get a bank card [debit card]; it all is easy.

The bad credit rating is going to have very little influence when you are in China. Chinese financial institutes are not sophisticated enough to do credit rating checks to the same extent as international banks. You will be able to open a basic account without any problem. You will get a standard POS debit card with Unionpay facility. Any foreigner that arrives here with a perfect credit rating (even executives of multinational companies) have a major problem obtaining credit facilities. If you so desire, certain banks will offer Gold Visa Debit (not credit) cards to foreigners. Again, they are highly unlikely to base the decision on credit rating.

As far as I know, choosing HSBC over any other bank is only relevant if you have a very good credit rating. You need to deposit a 6 figure sum to be able to have a credit card with them. Forget about getting a credit card in China. Getting a visa card is pretty much impossible for foreigners.