While we currently have support for importing GLTF2 assets via the Assimp plugin, the support is not complete because we do not support the expected MetalRoughness material and it's image channels that are expected by the format.  Once we have a suitable material to generate, it should be trivial to conditionally query the material properties expcted by GLTF2.  The version of Assimp we are using has all the necessary extensions, we just need to have a proper material to set them on.