Is there a shuttle bus or public transportation from PVG to South Bus/Railway Station?

Yes, you can take the direct shuttle bus line 7 to arrive at South Railway Station. The operating hours are from 06:30 to 21:30 with the frequency of around 15 mins. The duration is about 1hr45mins. And the ticket fare is around CNY 20 per person. After arriving, walk southeast around 750 yards to get to the South Bus Station.