androgynous; having both male and female characteristics
Describes a person, appearance, or quality that blends masculine and feminine traits. The glosses 'isosexual' and 'amphoteric' are technical terms from biology and chemistry respectively, and are not common in everyday use.
His fashion is very androgynous and doesn't give a sense of gender.
That model has an androgynous charm.
Compound of 両性 (ryōsei, 'both sexes') + 的 (-teki, '-like, -ic'). The base 両性 is itself from 両 (ryō, 'both') + 性 (sei, 'sex, gender').