S1 visa converted to work Z visa

Hi i want to ask you something. Could you please answer if u know smth about it. I am Uzbekistan citizen who is living in China. i have a work Z type and my wife is holding family visa which is S1 type. She wants to apply for a work Z type. Can she transfer her family visa to work Z type directly here in china. We are in china now. Or should she go to Uzbekistan to confirm it with Chinese embassy in Uzbekistan?