Can I still work full-time in China if I am ready or emigrate? Does the company still need to pay 4 gold for this?

Of course, you can do it during the preparation, but if you have left your job and gone abroad, you can't work full-time in China. Of course, if you are a multinational company, you can say that you work in an overseas office, which is feasible, but ordinary small companies (state-owned enterprises) can't.