There ARE hermaphrodites. They are few and far between but they do exist.
“The true hermaphrodite has both testicular and ovarian tissues present in either the same or opposite gonads. Both the external genitalia and the internal duct structures display gradations between male and female. … Two-thirds of true hermaphrodites are raised as males.” [https://www.caniry.com/how-common-is-hermaphrodite-in-humans/]
These people are intersex. Probably by absorbing their fraternial twin in the womb. They are sterile.