There are a few ways to distinguish between the two.
Once installed Google Workspace Add-ons(GWAOs) are accessible from the icon toolbar on the right of your screen, whereas Editor add-ons are accessible from the drop down menu.
GWAOs have a limited set of widgets and fairly narrow ways in which you can interact with them. With Editor add-ons developers can leverage HTML/CSS to create custom UIs.
Google Workspace add-ons are applicable to Gmail, Drive, Calendar, Docs, Sheets and Slides. Editor add-ons are applicable to Sheet, Docs, Forms and Slides.