Repro steps:
1. In a project, create a new shadergraph asset.
2. Change surface setting from 'opaque' to 'transparent'.
3. Save asset.
4. Create a material from the graph asset.
5. Create a new 3d object in the scene.
6. Assign the material to the object in the scene.

Notes:
-Repros in both render pipelines
-Repros in 2018.2 and trunk
-Repros with all blend modes
-Selection outline is mapped to the scene view screen and scales with the window.