Is it necessary to pay personal income tax for remittance from Hong Kong to the Mainland?
For the remitter, there is no need to pay, and no country needs to pay personal income tax for remittance.
For the payee, it is not necessary to pay, because even the labor income abroad has already paid personal income tax according to the local laws of foreign countries, and there is no need to pay a tax if it is repatriated to China.