[name_f]Roxanna[/name_f] “Roxy” is fabulous, and you have a great list! Here are some thoughts…
[name_f]Claudia[/name_f]–I love [name_f]Claudia[/name_f] and think it deserves more use! Would you consider a stretch nickname (Clio/Coco/Lola/etc.)?
[name_u]Simone[/name_u]–Ditto [name_f]Claudia[/name_f] (love in general and with Roxanna!), although I’m having even more trouble with nicknames for this one.
[name_f]Moira[/name_f]–Ruined by the Schitt’s [name_u]Creek[/name_u] character for me, but a beautiful name if you don’t have that association!
[name_f]Valerie[/name_f]–Doesn’t stand out to me as having the same spunk and energy of [name_f]Roxanna[/name_f], but still very pretty!
[name_f]Sabrina[/name_f]–Feels like a natural sister for [name_f]Roxanna[/name_f]! Nickname Bee/Bri/Bria/Nina/Rina?
[name_f]Felicity[/name_f]–Gives me softer vibes than [name_f]Roxanna[/name_f], but lovely and full of personality!
[name_f]Juliette[/name_f]–This isn’t my favorite from your list on its own, but I do think Jet/Jette would be a pretty fabulous counterpart to [name_f]Roxy[/name_f]! I also adore [name_u]Julie[/name_u] although it has a bit of a different vibe.
[name_f]Francine[/name_f]–Perfect with [name_f]Roxanna[/name_f] and [name_u]Frankie[/name_u] would be so good with [name_f]Roxy[/name_f]! I also like Francie/Frannie. This is probably my favorite option from your list.
[name_f]Clarissa[/name_f]–Not my favorite from your list (feels a little too frilly to me I think?) but still very pretty!
Other ideas, repeats are agreements…
[name_f]Aurelia[/name_f] → [name_u]Auri[/name_u], [name_f]Goldie[/name_f], [name_f]Lia[/name_f], [name_u]Ray[/name_u]
[name_f]Aviva[/name_f] → [name_u]Avi[/name_u], [name_f]Via[/name_f], [name_f]Vivi[/name_f]
[name_f]Bernadette[/name_f] → [name_f]Birdie[/name_f], [name_f]Etta[/name_f]
[name_f]Callista[/name_f] → [name_f]Calla[/name_f], [name_f]Callie[/name_f], [name_f]Lissy[/name_f]
[name_f]Clementine[/name_f] → [name_f]Emmy[/name_f], [name_f]Lettie[/name_f], [name_f]Leni[/name_f]
[name_f]Cornelia[/name_f] → [name_f]Cora[/name_f], [name_f]Nell[/name_f]
[name_f]Cosima[/name_f] → [name_u]Coco[/name_u], [name_f]Cosy[/name_f]
[name_f]Delilah[/name_f] → [name_f]Della[/name_f], [name_f]Lilah[/name_f]
[name_f]Dorothea[/name_f] → [name_f]Dottie[/name_f], [name_f]Thea[/name_f]
[name_f]Georgia[/name_f] → [name_u]Georgie[/name_u], [name_f]Gia[/name_f], [name_f]Gigi[/name_f]
[name_f]Gwendolen[/name_f] → [name_f]Gwen[/name_f], [name_f]Leni[/name_f]
[name_f]Harriet[/name_f] → [name_f]Etta[/name_f], [name_f]Hattie[/name_f]
[name_f]Henrietta[/name_f] → [name_f]Etta[/name_f], [name_f]Hattie[/name_f]
[name_f]Imogene[/name_f] → [name_f]Immy[/name_f], [name_u]Mo[/name_u], [name_f]Gigi[/name_f]
[name_f]Leonor[/name_f] → [name_f]Leni[/name_f], [name_f]Lola[/name_f], [name_f]Nora[/name_f]
[name_f]Magnolia[/name_f] → [name_f]Maggie[/name_f], [name_f]Nola[/name_f]
[name_f]Marigold[/name_f] → [name_f]Goldie[/name_f], [name_f]Mari[/name_f]
[name_f]Marina[/name_f] → [name_f]Mari[/name_f], [name_f]Mina[/name_f], [name_f]Rina[/name_f]
Maristella → [name_f]Mari[/name_f], [name_f]Stella[/name_f]
[name_f]Matilda[/name_f] → [name_u]Mattie[/name_u], [name_f]Millie[/name_f], [name_f]Tillie[/name_f]
[name_f]Ophelia[/name_f] → [name_f]Effie[/name_f], [name_f]Lia[/name_f], [name_u]Ollie[/name_u]
[name_f]Ottilie[/name_f] → [name_f]Lottie[/name_f], [name_u]Ollie[/name_u], [name_f]Tillie[/name_f]
[name_f]Paloma[/name_f] → [name_u]Dove[/name_u], [name_f]Polly[/name_f], [name_f]Lola[/name_f]
[name_f]Pauline[/name_f] → [name_f]Polly[/name_f], [name_f]Poppy[/name_f]
[name_f]Philippa[/name_f] → [name_f]Pippa[/name_f], [name_f]Poppy[/name_f]
[name_u]Romilly[/name_u] → [name_f]Milly[/name_f], [name_u]Romy[/name_u]
[name_f]Samara[/name_f] → [name_f]Mara[/name_f], [name_f]Mari[/name_f], [name_u]Sami[/name_u]
[name_f]Tabitha[/name_f] → [name_f]Tabby[/name_f], [name_f]Tia[/name_f]
[name_f]Tallulah[/name_f] → [name_f]Lula[/name_f], [name_u]Tali[/name_u]
[name_f]Verity[/name_f] → [name_f]Vera[/name_f], [name_f]Vivi[/name_f]
[name_f]Veronica[/name_f] → [name_f]Ro[/name_f], [name_u]Roni[/name_u], [name_f]Vera[/name_f], [name_f]Viva[/name_f]
[name_f]Virginia[/name_f] → [name_f]Ginny[/name_f], [name_f]Via[/name_f], [name_f]Vivi[/name_f], [name_f]Viva[/name_f]
[name_f]Winifred[/name_f] → [name_u]Freddie[/name_u], [name_f]Winnie[/name_f]
[name_f]Zahara[/name_f] → [name_f]Zara[/name_f], [name_f]Zari[/name_f]