[2D] Check if 2 parts are touching in an update loop?

Hello, Unity Answers. Lately I've been trying to make a game where you can place 2D parts down on a grid to create things. I need to make my editor script so that when you're placing a part it doesn't allow you to place it so it overlaps other parts. IsTouching doesn't work if I call it in an update loop, and OverlapCircle doesn't appear to either. Is there a way to do it?