Images that do not have a DxO Optics Module available need special attention because the sharpening, distortion correction, etc need to be applied manually.
Because they need special attention its kind of necessary to be able to easily locate them. Unfortunately there does not seem to be an easy way to sort or filter based on the availability of an optics module.
This can kind of be worked around by sorting by Camera or Lens, but this is really only helps work round the problem, its not really a final solution.
It seems like it would be very easy to add a new filter to allow raw images without a DxO Optics Module to be quickly and cleanly isolated for special attention.