Legends speak of an intelligent Orc who found the Heart of Aszune. This is the essence of her heart, precious to the Night Elves. It has the power to heal the Hero who wields it. This item is permanent.
The Heart of Aszune was found in Stonetalon Peak by Thrall, mere months before Kael found this item in the dungeons of Dalaran. So there's no way that there could be "legends" told of it, nor that the essence of Aszune could have been transported across the continent during that period of time.