Are you using the appropriate version of the exporters? If you are using an old version of UE such as 4.27 you should make sure to be using a datasmith exporter versions that are compatible with UE 4.27.
Are you using the appropriate version of the exporters? If you are using an old version of UE such as 4.27 you should make sure to be using a datasmith exporter versions that are compatible with UE 4.27.