A rigid body object without a mesh property?

I have a class inheritance system where the parent class has a Static Mesh and a Sphere Collision as its child.
image

The mesh will be different in every child. But when the mesh is too big or too small and if I want to scale it, naturally the collision is object also affected.

I tried to make mesh and collision components siblings under a parent physics object but I couldn’t find anything representing a rigid body object without its own mesh.

I tried having another dummy Static mesh as the common parent but without a mesh, physics wouldn’t affect it.

PS: In Godot, what I am trying to achieve can be done like this:
image

I also realized that using my parent-child structure, you cannot rotate the mesh.