I recently read Ninjas: 1000 years of the Shadow Warriors by John Man, which was interesting, but in talking about pop culture with a friend, one thing that came up that wasn't really mentioned in the book was the concept of Kunoichi (female ninjas) Do they have a basis in history or are they really just a modern pop culture fabrication?
Before discussing the possible existence of female ninjas, it's really necessary to consider whether ninjas, as a group, existed at all. The evidence is pretty flimsy. While you're waiting for further answers, you might like to review some earlier discussions of this problem, such as:
How many koku would a ninja in medieval Japan get paid for a typical assassination?, with u/NientedeNada
The respective roles of Ninja and Shinobi, with u/asiaexpert