1. Create a mod, which depends on another Workshop mod.
2. Publish your mod to the Workshop, and download it to your games mods folder.
3. Make some observable changes to a locally loaded resource from your mod (so not a world, which would have entities streamed from the server), like e. g. modifying a material.
4. Run the Dedicated Server Tool, using this as params for both server and peer client:
> -addonsDir "PathToProjectsFolder,PathToDownloadedModsFolder"
Both paths need to be specified, because the application needs to find both the edited project and the downloaded dependency from your mods folder.
5. The game will appear to start correctly, but it is possible you will not be able to observe these changes on the client side, because the client loaded the downloaded version of your mod from PathToDownloadedModsFolder, instead of the editable version from PathToProjectsFolder (like the server application correctly did).