You can use mirror handles to mirror a symbol about its center. The mirror handle appears at the right center of a symbol's range box. Dragging the mirror handle across the center of a symbol's range box causes the symbol to mirror about its center in dynamics. A center line for the X and Y axis appears through the range box of the symbol. The axes appear as solid when the pointer crosses one or both axes.
When you manipulate a symbol, you see the same behaviors unique to that symbol that existed when you placed the symbol in the document.