Can the residents of China buy tokens if they live in another country?
i assume you can, but wait for an official answer. As far as i know you need to respond to the law in the country you are now buying from.
You may need to prove where you actually live.
Some of the successful ICO uses KYC process to avoid breaching any law, if you lived in another place and your ID says your from china they might deny you in joining the ICO.