50/50 components with vertically dynamic placeholder images

I am looking for a solution for 50/50 (text/image) components to have placeholder images that are vertically responsive to the images placed. Ideally we do not want to detach the component.

Currently we have a placeholder image, so that images created in frames on the side can be quickly copied as a png and be pasted as placeholder in the component. However, since our images vary in height once they’re placed they fill with additional transparency. This is creating a lot of dead space for the mobile designs specifically.

Wondering if anyone has found a solution for this or thoughts on a different way to handle this?