Great news! This is exactly what I came here to find out. Unity, but also other apps - a good obj that we can convert to USDZ to put our objects in AR, particularly architectural models.
Just to be clear - Are you changing the obj export from vertex colors to texture with material? I just struggled for a while to find a conversion process. Close but no luck in Meshlab.
Can you point us to a conversion method/tutorial while we are waiting for the new version? Thanks!