The tentacles of either one of those anemones can reach further than you can imagine. If they start stinging one another they can severely hurt if not kill each other. That is why it is normally recommended that only one anemone per tank, unless it is a large tank (6ft). But with that said, it is up to the anemones, how territorial they are. If they feel the other anemone is taking their food, they will start stinging the other.
So my answer to you would be no, it is not idea, but if you feel you really want two in your tank, try to establish them on opposite sides of the tank. You might be alright, but keep an eye on them. Check for signs of stinging, if you see one is not doing as well as before, get it out, and find a new home for it.