Tehran is 12.5 hours ahead of Anchorage
There is no standard 8-to-6 overlap. Someone joins early or late.
Tehran is 12.5 hours ahead of Anchorage, so their typical working days don't line up at all. Plan on one side joining outside normal hours. A recurring slot that trades off between early mornings and late evenings usually works best. Just remember Anchorage changes its clocks for daylight saving and Tehran doesn't, so confirm the overlap whenever the seasons turn.