When you're ready to add a Sketchfab model to your ArtStation profile, click Upload in the top-right corner and choose New Artwork. Of the options there, you'll be able to choose Sketchfab and embed one of your models by entering your Sketchfab model URL.
Sketchfab URL parameters like preload and autostart are supported in ArtStation. Just add them to the end of your model URL!
The Model Inspector is not accessible when the Sketchfab viewer is embedded on ArtStation.