Formulaic sibling names help

I’m trying to find a sister name for [name_f]Rosamund[/name_f] nn [name_f]Rosa[/name_f] and Ingalill nn [name_f]Inga[/name_f] (characters). The names are super perfectly formulaic: eight letters, three syllables, the first two a 4-letter nickname ending in a, the last ending in a consonant. Are there any more girls’ names in existence that will work with this ridiculous sibset?

[name_f]Susannah[/name_f] (Susa)
[name_f]Annabeth[/name_f] ([name_f]Anna[/name_f])

Some of the nicknames are less obvious, but:

[name_f]Lavender[/name_f] nn [name_f]Lana[/name_f]
[name_f]Arianwen[/name_f] nn [name_f]Aria[/name_f]
[name_f]Marigold[/name_f] nn [name_f]Mara[/name_f]
[name_f]Margaret[/name_f] nn [name_f]Etta[/name_f] or [name_f]Mara[/name_f]
[name_f]Kathleen[/name_f] nn [name_f]Lena[/name_f]
Allifair nn [name_f]Alla[/name_f]
[name_f]Altalune[/name_f] nn [name_f]Luna[/name_f]

[name_f]Briallen[/name_f] nn. [name_f]Bria[/name_f]
Elsabeth nn [name_f]Elsa[/name_f]
[name_f]Rhiannon[/name_f] nn. [name_f]Rhia[/name_f]

And these almost follow the rule, but the nicknames don’t end in -a:

[name_f]Ceridwen[/name_f] nn. [name_u]Ceri[/name_u]
[name_f]Winifred[/name_f] nn. Wini

Ilsabein - last syllable rhyming with shine, nine or [name_m]German[/name_m] nein.

I love the suggestion of [name_f]Altalune[/name_f], but I’d suggest the nn [name_f]Alta[/name_f] so it would even better fit your criteria.

[name_f]Rosamund[/name_f] nn [name_f]Rosa[/name_f] and Ingalill nn [name_f]Inga[/name_f] &

Aaralyn/Airalyn nn [name_f]Aira[/name_f]/Aara
[name_f]Arianell[/name_f] nn [name_f]Aria[/name_f]
[name_f]Delancey[/name_f] nn Dela
Elsabell nn [name_f]Elsa[/name_f]
Elsaneth nn [name_f]Elsa[/name_f]
[name_f]Milagros[/name_f] nn [name_f]Mila[/name_f]
[name_f]Mirabell[/name_f] nn [name_f]Mira[/name_f]