Warsaw 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 Warsaw.
The hours that work for both Brasília and Warsaw are 8:00 AM to 2:00 PM (Brasília) and 12:00 PM to 6:00 PM (Warsaw). Plenty of room to work with: 6 hours of daily overlap means you can prioritise people's preferences over the clock. Note the seasonal wrinkle: when Warsaw is on daylight saving and Brasília isn't, the gap between them grows or shrinks by an hour.