Way back when I did a lot of portraiture (70's and 80's), I hated dealing with eyeglasses. My solution was to hit the local optometrists and ask for donations of old glasses or discontinued frames. I had a collection of about 70 pair and would have my customers find a pair they liked, or were close to their actual glasses, and then shoot them in just those frames with no glass in them, problem solved. Sometimes I would actually remove the glass from a clients glasses if they were metal frames because doing so with a jewelers screwdriver was easy, I even returned their glasses to them properly cleaned as well. Eyeglass reflections were never an issue after that.