Sure. You could put two different flavors in the same cart-tank if that suits your fancy. Putting on a cart-tank of a different flavor will just take some
vaping to get the old flavor out, the mix of the old and the new, and then the new flavor starts coming through.
Now, if the old flavor had menthol or cinnamon, it may hang in the atomizer for more than a few cart-
tanks, but that doesn't mean you have to eat your tomato apart from your hamburger as they may taste great together... (May not taste great together too, but there is only one way to find out.)