How do I link a shape from one composition into a crop for a different composition

[Maddi38892594aoka]

I have rectangular footage that I need to take multiple square crops from and to figure out what crops I want to take I am using the shape tool to draw boxes over the footage. I can obviously just create a new composition and try to match the scale/zoom and position but I'm wondering if there is a way to link the shape layers in the Cropping composition to the actual cropped compositions so that if I want to change the placement, it will carry over to the crops. I've attatched some screenshots that show what I mean (with placeholder footage). I've tried using expressions to link the position/scale but I'm finding it really confusing. Anyone have any ideas?