Idea: when you click resize, you could resize it, but navigating back to a previous size would keep the assets in the location and size or visibility that you created in that size. This way you could have multiple versions of the project to export for necessary platforms.

it would suggest it work like layer comps in photoshop. Instead of labeling the layer comp, you could just custom name the size. That way I can have a version for IG, FB, and a banner for YT all in one place instead of duplicating the project. This way I also keep all the assets the same.