Try printing 1/2 or a third of the exposure sharp then back off the focusing  knob a tiny bit.  Diffusion above the negative does vertually nothing to spread the high lights into the shadow. Remember you are focusing on the grain. To soften it back off on the focus.  None of the methods are very good in my opinion and will never come close to the look of a soft focus lens.
See Jim Galli, he has an old Wolensak copy of a Pinkham and Smith lens that he might part with to the highest bidder!  

    Charlie............