The Graeco-Egyptian goddess long-termed Baubo, more recently identified as Omphale1, exhibiting her genitalia was not mentionned by Petrie2 and Andrews or Wilkinson3 do not refer to her. There are few amulets of Omphale in striking contrast with the numerous ithyphallic ones

Carnelian
H 1.2, W 1.2, D 0.6
Ptolemaic-Roman
Period
MET #30.8.346
Unscaled Picture

Blue glaze H 2.8, W 2.2
Roman Period
© 2013 Musée du
Louvre/Antiquités
égyptiennes #E 23646

Green/yellow glazed with wings
H 3.8, W 3.0, T 1.1 Roman Period
© 2013 Musée du Louvre/
Antiquités Égyptiennes #E 14196

References

1See the description of MET #30.8.346
2Petrie W F M. Amulets, 1914, p. 37 and Figs. 169e,f
3Omphale was not mentioned by Wilkinson R H, Ref #37