Just makin sure i understood correctly (and i think i did), but making sure before booking flights.

Im going in November to visit Bauma China in Shanghai for few days, total time in China approx 72-84 hours, flights depending.
Schengen passport.
Itinerary would be SIN-HKG-PVG-HKG-SIN, i think the depart to HKG (transfer) is the red flag, even tho my destination is SIN, right?
I was going to book from CX (due to OWE) but maybe i need to take other way PVG-KUL-SIN on MH (times arent that great) due to the restrictions.
Or does visiting a trade show constitute for something you need visa for? Getting one is not a problem, the inconvenience of going to embassy for interview/passport collection is.