Combining a projected texture with a render texture

I am trying to achieve an effect similar to the blob shadow (picture 1), but we want to use a render texture in a similar way to picture 2 except projected onto the mesh rather than a texture being displayed on a cylinder above the mesh.

I am trying to figure out if there is a way to project a texture on a mesh (projected in the same way the blob shadow is projected like a circle) and the image being projected is a render texture. For example, the blob shadow projector projects a black circle on anything, but I don't want it to be the black circle, I want it to be the render texture.

In short, I want it to look like the blob shadow, but with a render texture.