Is it possible to manage Drupal running on a Windows server using drush on linux via a Samba mount?
In your case, 'os' =&gt; 'Linux'.  This variable tells Drush how to do things such as filesystem path escaping.  As you supposed, this variable is primarily used during remote calls, but I believe it may occasionally be referenced when building commands that are used locally.

I have never tried to set up Drush as you describe above; in theory, it should be possible, as long as you can connect to the database, but you might run into some problems.  Post issues in the Drush issue queue if you find bugs.  PRs with fixes would be particularly welcome.