Oslo is 6 hours ahead of Montreal
Best overlap: 8:00 AM to 12:00 PM in Montreal is 2:00 PM to 6:00 PM in Oslo.
Keep meetings inside 8:00 AM to 12:00 PM in Montreal — that maps to 2:00 PM to 6:00 PM in Oslo. With 4 hours of overlap, 8:00 AM in Montreal (2:00 PM in Oslo) is a comfortable, repeatable slot for both sides.