Geneva is 4 hours ahead of Brasília
Best overlap: 8:00 AM to 2:00 PM in Brasília is 12:00 PM to 6:00 PM in Geneva.
Aim for 8:00 AM to 2:00 PM Brasília time — that's 12:00 PM to 6:00 PM over in Geneva. With 6 hours of daily overlap, these two cities are an easy pairing; almost any reasonable hour works. Because Geneva and Brasília don't both observe daylight saving, plan to re-check the overlap around March and November.