Neutron transmission spectroscopy has become a promising operando characterization method for multi-phase structures with multi-textures in bulky materials. To further advance this method, we propose incorporating additional information from the magnetic scatterings with characteristics that differ from those of the conventionally used nuclear scatterings. To illustrate this, we measured the transmission spectra of polarized neutrons on ultra-fine-grained high-carbon steel, where we found the contribution of magnetic scattering, which has features different from that of nuclear scattering. Finally, future issues are discussed for practical utilization for characterizing multi-phase materials.