Riyadh is 2 hours ahead of Hamburg
Best overlap: 8:00 AM to 4:00 PM in Hamburg is 10:00 AM to 6:00 PM in Riyadh.
Aim for 8:00 AM to 4:00 PM Hamburg time — that's 10:00 AM to 6:00 PM over in Riyadh. Riyadh is 2 hours ahead of Hamburg, but you still share a generous 8 hours of overlap, so scheduling is easy and there's room to move a meeting when you need to. Remember that Hamburg shifts for daylight saving and Riyadh doesn't, so recalculate the overlap after each clock change.