How about Zilla (or Zillah) I know a Zilla, I think it's lovely.
Or what about Zia or Zyah
I really like Elodie
Or maybe Corinna?
This baby names website is really good for variants. So if you like the name Anna for example but want a more unusual version it has
"Variants:
Ana, Anique, Anja, Ann, Annabeth, Annah, Annalee, Annamarie, Anneke, Annemarie, Annet, Annica, Annika, Annmarie, Anoesj, Anouska, Hania and Nani.
also related names Anabel, Annabel, Audriana, Ayanna, Christian, Kiana, Leanna, Luana, Solana and Anastasia.
Baby names that sound like Anna are Agna, Aina, Anya, Ania, Anny, Anni and Anne."