Brasília is 4 hours behind Warsaw
Best overlap: 12:00 PM to 6:00 PM in Warsaw is 8:00 AM to 2:00 PM in Brasília.
Both teams are at their desks between 12:00 PM to 6:00 PM in Warsaw and 8:00 AM to 2:00 PM in Brasília. 6 hours of shared hours is more than enough — slot meetings wherever they're most convenient for the people involved. One seasonal catch: Warsaw springs forward and falls back, but Brasília doesn't, so the gap changes by an hour for several months of the year.