No. Steel covers exactly zero of its weaknesses, so it wouldn't work well on Musharna.
Due to the coverage options it gets being every type but Fairy and Normal, most people use HP to cover weaknesses. In Musharna's case, a Dark (for Ghost/Dark) type HP would probably work best, or Fire (for Bug). HP is also used to cover common threats, so an Electric, Fighting, Grass or Ice HP will probably work as well.