Here are some possibilities you might consider:
* Anya: This name is of Slavic origin and means "grace" or "favor". It shares a similar sound and feel with Aaron.
* Aarina: This is a rare name that combines the sounds of Aaron and Ariana.
* Arona: This is a variation of the name Aaron, potentially used in some cultures.
Ultimately, the best feminine form of Aaron depends on your personal preferences and what feels right to you.