Your post has no background information about what you try to do. From the sound of it, the question does not look right. Mailing RMB to oversea? It does not look, smell and sound right!
An ordinary Chinese citizens have annual limit of convert RMD to $50K USD and send the money overseas Why are you not looking at this option? So the answer could be that you have much more than $50K USD equivalent of RMB to move. Then the question is how much. Even you move the RMB to US, you still will have trouble to exchange to USD since there is currency reporting requirement in US noted in 柠檬椰子汁 post.
I was just joking that it is 'No praublem'. It is a problem! My advise to you is to obey the currency control regulations and laws in China and other countries as well. Good luck.
