Where have you found those? Can you toss up a link?
And if memory serves Neo had regular sunglasses, it was Morpheus that had the ones that just sort of rested on his nose. Maybe you could get the bridge of your nose peirced and have magnets on it. Then you just clip them on there!
If your glassea are uncomfortable under your helmet, then you have the wrong helmet, that's one of the things you should test for when you buy one. I've got a HJC CL-14 and my prescription frames fit under with no worries. If I'm in a rush and they go on "stick-eyed" then it's uncomfortable, otherwise I don't even notice they are there. You might consider looking at different makes or models.
Finally, you could always just get a tinted visor, I'm in love with mine.

Of course I'm generalizing from a single example here, but everyone does that. At least I do.
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