Players should know that Zul’Gurub trinket effects can’t stack according to Community Manager Caydiem.
This is indeed true. Zandalarian Hero Charm and the Talisman of Ephemereal Power can no longer be stacked, along with most of the other trinkets from Zul’Gurub and the level 50 class quest trinkets. A simultaneous cooldown will prevent these items from being used simultaneously.
Let me explain the cooldown further, since there are questions. Use of these trinkets will trigger a cooldown equal to the duration of the effects—which means that you can indeed use one directly after another.