Unfortunately glasses are one of the things that are very complicated. They are prone to extreme distortion and will loose their shape easily with every face morph you dial in, if you use them as clothes. There are only a few "glasses-clothes" made by users and unfortunately none of them are working as flawless as the two magically working build-in female glasses from the very beginning of VaM. On the other hand, there are some glasses as custom unity assets out there, which will work for males too, and without distortions. But assets for body accessories were never easy to use and therefore not as popular as clothes. There are some plugins to make the usage of assets a bit more easy. So if you eagerly want one of your male looks have glasses in some selected scenes, this would be the way to go.
In the last two years of VaM development, there were many requests for more of those "magically" build-in glasses as clothes for male and female, but they never had a high priority compared to other highly demanded stuff or functions. Unfortunately IMHO.