I painted the window on my garage back door (nobody can see it anyway).
How about that “frost” stuff in a can for Christmas? You might still be able to find some on sale - I wonder if that would frost the windows enough to prevent seeing through, but still let some sunlight in. Kind of like the frosted glass in my bathroom window?
Or - if you have the bucks - replace them with frosted glass.
I've used it and it works fine, but if a curtain or hands are bumping the window a lot, then it wears off, it is excellent for someone who wants to try the idea first.