Hey, look at the Answer of this Question. He gave a pretty good example on how to achieve this.
He converst the 3D Space to 2D and checks if the positions are inside the retangle. You can see all his Blueprints and a small Code snippet for the test in his answer:
If you don’t want to code, you can make his C++ function in Blueprints too. Just some branches that check if a number is higher or lower than another.
If you need help, just ask me (: