Is there a way to turn existing identical objects with different transform to a nested prefab in one step?

Please see attached image. New to Unity, working on an existing project that I did not create.

Is there a way to turn the "Window Panes" Parent Object and all it's children to a nested Prefab in a single step? There hundreds of "window_pane(#)" models and they all have identical properties except for their transform position. I need to change the Material for all "window_pane(#)" models and need to know if there's a way to do it once and apply to all.

I've been searching nested prefabs online but I'm getting the sense that it only works if I'm creating a project from scratch. I'm lost to whether there's way to do this on an already existing project.