I don't think civilians would know anywhere near detail level on how China recruits people in enemy nations.
I'd guess a lot is done through international business meetings and conferences. MSS has a basic level of infiltration globally from signal intelligence and just having a ton of spies everywhere as well, based on the data, they identify if a target is a potential defector and only then would they contact you. Since data analytics is one of China's main strengths, there's probably a very well worked out method for how each case is approached.
As for how they contact, it could be with a physical visit to China, but also to pretty much any country in the world or even just in someone's own home. Would depend on how high value the defector is.