Back from the clean Singapore tube to get on the French underground. The latter is rightly so more recent than the former indeed, however this is another type of stress to add i.e. the touch.
However, the first touch you might find stressful or not is the hand shake. In some culture a simple “hey” when you enter a room full of people might be the only way to greet people, in some others a detailed kiss on the cheek is more the norm as for other cultures a hand shake will do. This is important because a greeting is how you break the ice at work or anywhere else. You might not feel like some strangers (clean enough?) kissing you on the cheek to say hello, you might go with a hand shake, but for some others you might be seen not doing so as distant and rude.
Some others might go for a hug or a bow in the Japanese culture with no touch at all. No touch sometimes is the standard. Touchy feely in some cultures is a sign of team work and giving a peck on the cheek between 2 males is a sign of friendship in some others. However these might not be the most stressful type of stress but more intrusive type of greeting.
And this added to other stresses like speech, can be enough not to open up and not be at ease at working in a company or living in a country. Here is a simple comparison.
In Australia people will greet you in business like: “Hi I am XXX how are you going?”. In France it will be more formal and be more like: “Good afternoon, Mr XXX, I am Mr XXX I am pleased to meet you (strong hand shake if possible)”. In some anglo-saxon country to say Mr or Ms or Mrs is a sign of formality only applied to very formal situation such as dealing with administration services, a justice department etc
How difficult will it be for a French person to deal with working in China? In fact it is a bit more obvious than this stereotype. It is said that people with a very strong home culture and identity will do well, probably not so well adapting to the local rules, but doing well doing away with the culture shock and stresses.