@op

What sort of transits do you have in mind?

-Int-int would be rare because there are nonstop flights on pretty much every a-b-c route (in which, b = Shanghai).
-for int-domestic and vv, you need to switch terminals unless the domestic flight is on 9c, and this requires a taxi or subway ride

SHA is much more convenient than PVG if Shanghai is your origin or destination.
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