Ooh, that's a great question. I'm not aware of that being an option yet, in order for that to happen there would need to be a material editor functionality—which there is a basic one in reality converter—I'm honestly looking forward to a more robust material editor within Reality Composer. I feel like once that is in place (or if Converter accepts video textures) then you'll probably see that kind of functionality.
Please do share if you get that figured out! 🙏