Portland is 9 hours behind Geneva
Best overlap: 5:00 PM to 6:00 PM in Geneva is 8:00 AM to 9:00 AM in Portland.
The hours that work for both Geneva and Portland are 5:00 PM to 6:00 PM (Geneva) and 8:00 AM to 9:00 AM (Portland). The shared window is only 1 hour — treat 5:00 PM in Geneva (8:00 AM in Portland) as the one fixed point and plan everything else around it.