Islamabad is 10 hours ahead of Ottawa
There is no standard 8-to-6 overlap. Someone joins early or late.
Islamabad is 10 hours ahead of Ottawa, 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 Ottawa changes its clocks for daylight saving and Islamabad doesn't, so confirm the overlap whenever the seasons turn.