If you are planning to use Datasmith to import scenes from Archicad to Unreal Engine, reading this page can help you understand how your scene is translated, and how you can work with the imported scene in Unreal Editor. It follows the basic process outlined in the Datasmith Overview and Datasmith Import Process, but it provides additional details on the Direct Link workflow and translation behaviors specific to Archicad.
This page describes how Datasmith imports scenes from Graphisoft Archicad into Unreal Engine.