Using a multisub material with substance materials in it with 3DsMax 2023 and then exporting with datasmith to UE5 does not export the substance material. It just skips all substance materials. Does datasmith support substance materials?
We do not support substance material in the exporter. we support to some extent, VRay, Corona, Mental Ray, Arnold.
You could try to convert to “Physical Material” in Max before exporting to UE
