From a physical point of view, that seems difficult. "One-way" mirrors still work by letting through only approximately half of the light, with one side coated sparsely with a reflective material. In order for the eyes to be obfuscated, the area behind the glass also has to be significantly darker than the other side. And, of course, the whole thing would darken your vision by only letting about half of the light through. It's not much, if any, better than normal sunglasses, really.

I thought about a polarising filter, like it's used on privacy-protecting screens, but people who are looking straight towards your glasses in an orthogonal angle to the glasses would still see your eyes perfectly, which is exactly what you'd like to avoid. Additionally, such filters tend to produce a darker image, too. Off the top of my head, I can't think of a viable solution for glasses, but I'm happy to be proven wrong. I hope that you'll find a solution to that specific problem.

Not a perfect solution answer here also, but I always like to look at the different lens treatment options when I get glasses - and I know you can get mirroring done in different strengths, which, if you got a pair of glasses made with a slight mirror effect and perhaps a small color tint (I got a pale purple tint once that didn't limit the incoming light) - that combo might be enough to obfuscate your eyes a bit without much darkening. I bet if you talked to a decent glasses shop they might be able to think of some ideas.

I just suck it up and wear dark glasses. It does my impair my limited vision some, but it's worth it for the reduction of awkward social encounters