Madrid is 5 hours ahead of Montevideo
Best overlap: 8:00 AM to 1:00 PM in Montevideo is 1:00 PM to 6:00 PM in Madrid.
Keep meetings inside 8:00 AM to 1:00 PM in Montevideo — that maps to 1:00 PM to 6:00 PM in Madrid. You share roughly 5 hours a day. That's enough for regular meetings, but treat the window as prime time and guard it. Because Madrid and Montevideo don't both observe daylight saving, plan to re-check the overlap around March and November.