Saw this at the Mr. Mike's restaurant in North Edmonton - an open hallway with multiple doors, each with moustache and lips (some also with wheelchair and baby logos).
Not perfect, as the signs are still based on a gender binary, but pretty good.
It provides the second best alternative to truly gender-neutral washrooms: single-user washrooms with dual gender signage. This means that transgender and non-binary patrons can go into any available washroom without anyone hassling them for being "in the wrong washroom" No one will hassle them for what door they go through, and no one will hassle them for which washroom they are actually in (cuz they'll be in there by themselves).