Aphroditos, the Trans Aphrodite worshipped widely in Amathus and Athens.
This particular pose, where a feminine deity lifts up their skirt or dress to reveal a phallus, is called the Anasyrma or Anasyromenos and was widely regarded as an apotropaic gesture, averting evil influences and bringing forth good fortune.
"There's also a statue of Venus on Cyprus, that's bearded, shaped and dressed like a woman, with scepter and male genitals, and they conceive her as both male and female. Aristophanes calls her Aphroditus, and Laevius says: Worshiping, then, the nurturing god Venus, whether she is male or female, just as the Moon is a nurturing goddess. In his Atthis Philochorus, too, states that she is the Moon and that men sacrifice to her in women's dress, women in men's, because she is held to be both male and female."
-Macrobius, Saturnalia (C. 431 CE)
This combination of masculinity and femininity in the same Deity and their assocition with the moon, both of which were considered to have fertilizing powers, was regarded as having an influence over the entire animal and vegetable creation.
They were often identified with Ermaphroditos (Hermaphroditus), the intersex child of Aphrodite and Hermes
Sources:
Koloski-Ostrow, Ann Olga; Lyons, Claire L. (2000), Naked truths: women, sexuality, and gender in classical art and archaeology, Routledge; pp. 230-231.
^ Freese, John Henry (1911). "Aphrodite" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. 2 (11th ed.). Cambridge University Press. p. 166.
Macrobius; Kaster, Robert A. (2011), Saturnalia, Volume 2, Harvard University Press; p. 58