A buffing wheel has a soft surface, so when used with polishing rouge will polish the metal. It won’t sharpen the edge, however, because the deflection of the felt won’t allow a fine edge to develop.
You need stiff leather or wood (or a sharpening stone) to develop the razorsharp edge.
A buffer wheel can be perfect for polishing the sides of the knife blade to a mirror polish, especially if multiple wheels are progressively used with finer and finer grades of polishing compound.