Help with twin girl names

Me and my husband are expecting twin baby girls in a few weeks. We already have a son called [name_m]Xavier[/name_m] [name_m]Theodore[/name_m].
We are very excited but are agonising over what to call them.

We don’t like matchy names and don’t want anything beginning with ‘X’ again. We both like quite modern, under-used names. We want a name that is uncommon of but not unheard of. Hubby dislikes unisex names (I don’t mind but I haven’t found any I like). We don’t really want same letter names.

Names that are off limits are: [name_f]Camilla[/name_f], [name_u]Wren[/name_u] and [name_f]Olivia[/name_f].

We both like but don’t love:
[name_f]Carrie[/name_f]
[name_f]Clara[/name_f]
[name_u]Sierra[/name_u]
[name_u]Carmen[/name_u]
[name_f]Bluebell[/name_f]

It’s hard for me to tell what you mean by modern and underused, but:

[name_f]Evangeline[/name_f]
[name_f]Margot[/name_f]
[name_f]Lila[/name_f]
[name_f]Catherine[/name_f]
[name_f]Willa[/name_f]
[name_f]Esther[/name_f]
[name_f]Edith[/name_f]
[name_f]Fiona[/name_f]
[name_f]Antonia[/name_f]
[name_f]Sylvie[/name_f]
[name_f]Ramona[/name_f]
[name_u]Carmel[/name_u]
[name_f]Maren[/name_f]
[name_f]Winona[/name_f]
[name_f]Louisa[/name_f]
[name_f]Alessia[/name_f]
[name_f]Corinne[/name_f]

[name_f]Adriana[/name_f]
[name_f]Alexandra[/name_f]
[name_f]Anastasia[/name_f]
[name_u]Ariel[/name_u]
[name_f]Athena[/name_f]
[name_f]Bianca[/name_f]
[name_f]Claudia[/name_f]
[name_f]Cora[/name_f]
[name_f]Juno[/name_f]
[name_f]Maxine[/name_f]
[name_f]Petra[/name_f]
[name_f]Roxana[/name_f]
[name_f]Vera[/name_f]

[name_u]Eloise[/name_u]
[name_f]Matilda[/name_f]
[name_f]Sienna[/name_f]
[name_f]Amelia[/name_f]
[name_f]Serena[/name_f]
[name_f]Natalia[/name_f]
[name_f]Aurora[/name_f]
[name_f]Arianne[/name_f]
[name_f]Olympia[/name_f]
[name_f]Alessia[/name_f]

I like [name_m]Xavier[/name_m] [name_m]Theodore[/name_m], [name_f]Margot[/name_f] [name_f]Emie[/name_f], and [name_f]Carys[/name_f] [name_f]Ingrid[/name_f]

[name_f]Anais[/name_f]
[name_f]Alina[/name_f]
[name_u]Arden[/name_u]
[name_f]Aster[/name_f]
[name_u]Eden[/name_u]
[name_u]Haven[/name_u]
[name_f]Mira[/name_f]
[name_f]Jade[/name_f]
[name_u]Juniper[/name_u]
[name_f]Kenza[/name_f]
[name_f]Kezia[/name_f]
[name_f]Leda[/name_f]
[name_f]Linnea[/name_f]
[name_f]Malia[/name_f]
[name_f]Rhea[/name_f]
[name_u]Seren[/name_u]
[name_f]Zoe[/name_f]
[name_f]Zella[/name_f]
[name_f]Zinnia[/name_f]
[name_f]Irie[/name_f]
Innara

Some suggestions based off your likes this and considering your don’ts:
[name_f]Ivy[/name_f]
[name_f]Lydia[/name_f]
[name_f]Sienna[/name_f]
[name_f]Cora[/name_f]/[name_f]Coralie[/name_f]
[name_f]Valerie[/name_f]
[name_f]Primrose[/name_f]
[name_f]Margot[/name_f]
[name_f]Christabel[/name_f]/[name_u]Christobel[/name_u]
[name_f]Yona[/name_f]
[name_u]Juniper[/name_u]
[name_f]Carys[/name_f]
[name_f]Luna[/name_f]
[name_f]Marigold[/name_f]
[name_f]Acacia[/name_f]

Twin pairings I like from this list:
[name_f]Ivy[/name_f] and [name_f]Luna[/name_f]
[name_f]Valerie[/name_f] and [name_f]Acacia[/name_f]
[name_f]Carys[/name_f] and [name_f]Ivy[/name_f]
[name_u]Juniper[/name_u] and [name_f]Marigold[/name_f]
[name_f]Lydia[/name_f] and Chistabel
[name_f]Yona[/name_f] and [name_f]Primrose[/name_f]
[name_f]Cora[/name_f] and [name_f]Margot[/name_f]
[name_f]Sienna[/name_f] and [name_f]Coralie[/name_f]

[name_f]Esme[/name_f]
[name_u]June[/name_u]/[name_f]Junia[/name_f]
[name_f]Tova[/name_f]
[name_f]Oona[/name_f]/[name_f]Una[/name_f]
[name_f]Noemi[/name_f]
[name_f]Eleni[/name_f]
[name_f]Linnea[/name_f]
[name_f]Aurelia[/name_f]

[name_u]Brooke[/name_u] and [name_f]Scarlett[/name_f]
[name_f]Alana[/name_f] and [name_f]Kara[/name_f]
[name_f]Caitlin[/name_f] and [name_f]Clover[/name_f]
[name_f]Danielle[/name_f] and [name_f]Stephanie[/name_f]
[name_f]Willa[/name_f] and [name_u]Ruby[/name_u]
[name_u]Harmony[/name_u] and [name_f]Rayne[/name_f]
[name_u]Sydney[/name_u] and [name_f]Sienna[/name_f]

From your list I really like [name_f]Clara[/name_f]. I would recommend [name_f]Dahlia[/name_f] or [name_f]Delilah[/name_f] for you.

[name_m]Xavier[/name_m], [name_f]Clara[/name_f] and [name_f]Dahlia[/name_f]
[name_m]Xavier[/name_m], [name_f]Clara[/name_f] and [name_f]Delilah[/name_f]

I love [name_f]Clara[/name_f] from your list, and [name_f]Bluebell[/name_f] as a mn: [name_f]Clara[/name_f] [name_f]Bluebell[/name_f].

[name_f]Margaux[/name_f]
[name_f]Elodie[/name_f]
[name_f]Brenna[/name_f]
[name_f]Nina[/name_f]
[name_u]Paisley[/name_u]
[name_f]Lacey[/name_f]
[name_f]Pippa[/name_f]
[name_m]Pippin[/name_m]
[name_f]Zelie[/name_f]
[name_u]Mirren[/name_u]
[name_f]Calla[/name_f]
[name_f]Luna[/name_f]
[name_f]Kerensa[/name_f]
[name_f]Greta[/name_f]

[name_f]Claire[/name_f]
[name_f]Sienna[/name_f]
[name_f]Leona[/name_f]
[name_f]Mila[/name_f]
[name_f]Hazel[/name_f]
[name_f]Pearl[/name_f]
[name_f]Acacia[/name_f]
[name_f]Uma[/name_f]
[name_f]Amalia[/name_f]
[name_f]Scarlett[/name_f]
[name_f]Valerie[/name_f]
[name_f]Marie[/name_f]