You can definitively adopt the approach we’re using for Mapper. In brief:
In mapper, we allow users to bless certain elements as revit (soon archicad and more) objects. E.g., an extrusion in Rhino can be assigned to be a wall, and then, when received in Revit, it will become a wall.
You can definitively do the same from “threejs” - the exact implementation depends on how your app allows for modelling; it’s a simple matter of attaching to your object a custom property with a specific pattern - we can help here. You can then send that to your own speckle server, or to ours - whatever is easiest - and then the end user can receive that model in revit via our connectors.