Hamburg is 2 hours behind Riyadh
Best overlap: 10:00 AM to 6:00 PM in Riyadh is 8:00 AM to 4:00 PM in Hamburg.
Shoot for 10:00 AM to 6:00 PM in Riyadh; your Hamburg colleagues will see that as 8:00 AM to 4:00 PM. Hamburg is 2 hours behind Riyadh, but you'd hardly notice — 8 hours of shared hours makes this feel like working in neighbouring time zones. Seasonal note: Hamburg uses daylight saving and Riyadh doesn't, so double-check the times in your own months — they can move by an hour.