Brussels is 6 hours behind Hong Kong
Best overlap: 2:00 PM to 6:00 PM in Hong Kong is 8:00 AM to 12:00 PM in Brussels.
For the smoothest call, aim inside 2:00 PM to 6:00 PM in Hong Kong, i.e. 8:00 AM to 12:00 PM in Brussels. With 4 hours to play with, a mid-window meeting keeps things balanced for Hong Kong and Brussels alike. Seasonal note: Brussels uses daylight saving and Hong Kong doesn't, so double-check the times in your own months — they can move by an hour.