I've seen and been in unisex bathrooms, it was well designed, that is each stall was closed off, they had urinals stalls. You couldn't see into any stall, they had sinks to wash your hands. And it worked great, you walked in, did your business in private and walked out. No problem.
A unisex public toilet, alternatively called a unisex bathroom, unisex lavatory, gender-inclusive toilet, gender-neutral public toilet, gender-neutral washroom, or unisex restroom is a public toilet that people of any gender or gender identity may use. Gender-neutral bathrooms benefit transgender populations and other people who exist outside of the gender binary; people with disabilities, the elderly, and anyone else who may require the assistance of someone of another gender; and parents who may wish to accompany their children to the washroom or toilet facility. More: en.wikipedia.org.