Geneva is 4.75 hours behind Kathmandu
Best overlap: 12:45 PM to 6:45 PM in Kathmandu is 8:00 AM to 2:00 PM in Geneva.
Book within 12:45 PM to 6:45 PM Kathmandu time (8:00 AM to 2:00 PM in Geneva) and both teams will be at work. That's a roomy 6 hours of common time each day, so finding a slot that suits everyone is rarely a problem. Note that Geneva follows daylight saving while Kathmandu stays put, so the times above drift by an hour seasonally.