After a decade of films in the MCU, there are still only two female Avengers: Black Widow and Scarlet Witch. Neither of them have their own films, though there is reportedly a Black Widow standalone in the making. "Captain Marvel" starring Brie Larson also comes out next year.
Women are often the girlfriend, wife, or mother. In film, a female character's worth is typically determined by their relationship to the male stars. With the success of films like "Wonder Woman," hopefully that will change.