Do you still need to come back to the mainland every year to apply for re-entry after emigration?

Those who immigrate to the mainland every year do not need to go through visa re-entry procedures. Visa re-entry procedures can only be handled when you go abroad for the first time, and you don't need it later.

Immigration and naturalization are two different concepts. Immigrants only get permanent residency in foreign countries, while naturalization means that you are a foreigner rather than a China (China does not recognize dual citizenship).

If you only have foreign permanent residency, such as American green card, Canadian maple leaf card, etc. You don't need any formalities to return to China, just show your China passport when you enter the customs.

If you have become a foreign national, you must obtain a Chinese visa to enter China (unless the naturalized country can enter China visa-free). Whether you need to apply for a visa every time you return to China depends on the type of Chinese visa you get. There are one-time visas and N-year multiple-entry visas.