Drag asset to scene (editor extension)

To allow dragging any asset types to the scene, I would like to implement an Editor extension. This would obviously aim at those asset types which are currently not draggable to the scene. The goal would be to have a custom instantion action of custom gameobjects.

Is there any Editor hook, to tie that functionality in ?

Hmmm you should be able to listen to the Drag & Drop input events in any Editor script, provided that this editor is already instantiated either with the corresponding type already in the scene or manually instantiating the editor script (there is some Editor utility method that does this). Sorry I can’t be more specific right now.

Personally I would just opt for a context menu item, either in the create menu or up top under Tools or a custom toplevel menu. This runs a script which can use Selection to get all the objects currently selected and do the appropriate thing. If you write this code to be called from elsewhere with a set of items you can then later refactor it into drag & drop - if you still need that. I often find that having such a menu item script is more than enough in most cases.