Movement outline

I am trying to make a movement range outline for my gridbased game, as can be seen in tactical rpgs like XCOM. https://imgur.com/8ae7cuC

XCOM Outline

I figured I could do this by procedurally generating a mesh and slapping some sort of outline shader on it with shadergraph. I've managed to generate the mesh:(white object around the selected character). https://imgur.com/EmRN2ImMoveMesh

However I can't figure out how to make the mesh transparent with an outline/edge glow.

Any ideas how I can achieve the effect I'm after, either by making a shader for the mesh or through some other means?

Thanks!