Brigantia

Brittania

Canola

Carme

Cethlenn

Ceto

Coventina

Damona

Devera

Egeria

Elbereth

Elentári

Empanda

Ennodia

Enyo

Epona

Erecura 

Ersa

Gondolin's list "Mythological goddess names for girls" of 20 great name ideas: Bia - Ersa!

Mythological goddess names for girls

This list strives to include all more-or-less usable mythological names for girls out there. This is a great resource for anyone looking for an unusual name with history and depth and will continue to get better as the list grows.
So far added: Celtic, Egyptian, Greek, Nordic, Roman and Tolkien deity names. If you have any additions, please send me a message!