Taipei is 13 hours ahead of Dallas

There is no standard 8-to-6 overlap. Someone joins early or late.

Taipei is 13 hours ahead of Dallas, which is far enough that a normal 9-to-5 in one city never reaches the other's working hours. One practical option: Dallas dials in early while it's still late afternoon or evening in Taipei. Remember that Dallas shifts for daylight saving and Taipei doesn't, so recalculate the overlap after each clock change.