Moscow is 1 hour ahead of Bucharest
Best overlap: 8:00 AM to 5:00 PM in Bucharest is 9:00 AM to 6:00 PM in Moscow.
Target 8:00 AM to 5:00 PM in Bucharest, which lands at 9:00 AM to 6:00 PM for the Moscow side. The overlap is wide at 9 hours, so you can protect mornings for deep work and still find plenty of meeting time. For part of the year the maths changes: Bucharest observes daylight saving, Moscow does not, shifting the overlap by an hour.