I haven't done international-domestic connections at PVG yet (I did LAX-CAN via Shanghai but my CAN leg was via SHA), but generally if you're flying MU or FM, you will have a fairly easy time connecting in PVG.

If you're connecting to another flight and you have a tight connection, usually there will be someone from MU at your gate who will meet you to help facilitate your transit through PVG. I've seen this with passengers on international-international connections, so this should also be the case with international-domestic connections.

The reverse though may be more difficult: you will not receive your international boarding pass until you arrive at the transit airport (which, in your case, will be PVG). When I did CAN-NKG-LAX, I had to go out and check in again. That said, I think you'll be fine.