Hi i replied in the other thread/forum. But briefly again for Hong Kong you need registration: Physiotherapists Board
It takes time (maybe 6 months) so start early, you need get all your documents, letters from your university and past employers to confirm your education, content of your courses, and your number of years of experience meet the minimum for Hong Kong. Once you collect all the information then you need submit, and make payment to the Hong Kong registartion board to consider processing your application. Hong Kong and China are different governments remember, if you did want China then in regards to Mainland China, it's not necessary if your work in a International Clinic (which most foreign physiotherapist would), but a Hong Kong registration would be OK for China.