Generally speaking, the overseas subsidiaries you mentioned should belong to the "non-resident enterprises" stipulated by the laws of China. According to the provisions of the enterprise income tax law, non-resident enterprises only need to pay enterprise income tax on their income from domestic sources. If all the business of your overseas subsidiary is abroad, you don't need to declare income tax in China.
Profits distributed by overseas subsidiaries obtained by domestic head offices shall be incorporated into their taxable income, and income tax paid by overseas subsidiaries may be reduced or exempted at the same time.