Version: 2019.3
public static void SetMainObject (Object mainObject, string assetPath);


mainObjectThe object to become the main object.
assetPathPath to the asset file.


Specifies which object in the asset file should become the main object after the next import.

All other objects in the asset become children of the main object. NOTE: This function modifies the importer object, not the asset itself. The next import reflects the change in the imported asset.