Tehran is 0.5 hours behind Abu Dhabi
Best overlap: 8:30 AM to 6:30 PM in Abu Dhabi is 8:00 AM to 6:00 PM in Tehran.
Plan around 8:30 AM to 6:30 PM in Abu Dhabi, which is 8:00 AM to 6:00 PM in Tehran, to catch everyone during office hours. That's a roomy 10 hours of common time each day, so finding a slot that suits everyone is rarely a problem.