On the size of sex differences in personality:

"When sex differences across multiple traits are combined using multivariate statistical methods, the global difference between the average profiles of men and women ranges between two and three standard deviations. This means that the personality distributions of males and females overlap by about 10%, which is close to the anatomical overlap between male and female faces (Del Giudice, 2013; Del Giudice et al., 2012). The comparison between faces and personality profiles is illuminating: while the sexes look fairly similar if one considers one anatomical feature at a time (e.g., the size of the eyes, the length of the nose), the difference becomes obvious as soon as one starts looking at whole faces of men and women."

The evolutionary context of personality development Marco Del Giudice (2017)