Nothing a foreign bank account, a VPN & an account on a European exchange can’t solve in all honesty.
If the exchange in question bans Chinese users I would advise against it.
There are a lot of things that can go wrong and nowadays a lot of them are simply preying on suspicious users, one failure of the kill switch in your IP, one bug in your VPN that gives a different country IP, and good luck with the support team and getting you funds back.
I've seen tons of such stories later both here and on Reddit, for exchanges this is a perfect source of income, not even 0.01% will be able to go and file a police complaint against or sue them and they know it.
If it's just a simple exchange between fiat<>btc, better ask a friend or a relative outside the mainland to do it for you, if it's day trading, find a platform that doesn't care about the rules and says that upfront.
I wouldn't be surprised if the Chinese government would commit entrapment by pretending to be a bitcoin seller or something.
I would be surprised if a lot of countries are not already present on all platforms with accounts and doing trades, probably some have managed to get mediator status.
Localbitcoins, 2014. I doubt that they haven't infiltrated all p2p exchanges in 7 years.