I am trying to set up my csproj files to search for dependencies in a parent directory by adding:
..
Seems like there was a fix recently Thus this works as well:
MY_PATH;$(ReferencePath)
This makes the assemblies in that folder to also show up in the "Add References..." window :)
And since you also might not want the assemblies to be copied into the output-folder, here an example on how to achieve this:
C:\Program Files\Unity\Hub\Editor\$(UNITY_VERSION)\Editor\Data\Managed\UnityEngine;$(ReferencePath)