Tourtist visa with domestic transfer

I am looking to fly Sydney - Nanjing (1.5 hours) - Shanghai (8 hours) - Japan.

I don't plan to leave the airports to transfer, but would like to confirm if I need to apply for a visa. I will need to fly a domestic route, so I expect I may need to pass through immigration in Nanjing which technially makes me ineligible for a transit G, as I will not got direct to a third country. I am travelling on an Australian passport.