Lagos is 1 hour behind Oslo
Best overlap: 9:00 AM to 6:00 PM in Oslo is 8:00 AM to 5:00 PM in Lagos.
Keep meetings inside 9:00 AM to 6:00 PM in Oslo — that maps to 8:00 AM to 5:00 PM in Lagos. Because you share 9 hours of the workday, there's no need to compromise; book the time that suits the meeting, not the map. Because Oslo and Lagos don't both observe daylight saving, plan to re-check the overlap around March and November.