Panama City is 2 hours behind Brasília
Best overlap: 10:00 AM to 6:00 PM in Brasília is 8:00 AM to 4:00 PM in Panama City.
For the smoothest call, aim inside 10:00 AM to 6:00 PM in Brasília, i.e. 8:00 AM to 4:00 PM in Panama City. Panama City is 2 hours behind Brasília, but with 8 hours of common ground you can hold morning or afternoon meetings without anyone working odd hours.