I love eclectic sister sets! I am so excited about this question! 
@Evergreeninrain
With one sister who’s got a traditionally masculine name and one sister who’s got a vintage feminine name, I think there are a few ways to go with a third sister. Another name in either style that you already have doesn’t quite seem right (because [name_u]Conner[/name_u], [name_f]Elsbeth[/name_f], and [name_u]Royce[/name_u] leaves
[name_f]Elsbeth[/name_f] out, but [name_u]Conner[/name_u], [name_f]Elsbeth[/name_f], and [name_f]Marianne[/name_f] leaves [name_u]Conner[/name_u] out). Here are some ideas for introducing a third style in to bring [name_u]Conner[/name_u] and [name_f]Elsbeth[/name_f] together.
[name_u]Conner[/name_u], [name_f]Elsbeth[/name_f], and…
word name
[name_u]Peace[/name_u]
[name_u]June[/name_u]
[name_u]Garland[/name_u]
[name_u]Lacy[/name_u]
[name_f]Opal[/name_f]
[name_f]Merrily[/name_f]
[name_f]Ginger[/name_f]
[name_f]English[/name_f]
[name_u]July[/name_u]
[name_f]Clementine[/name_f]
[name_f]Flower[/name_f], [name_f]Fleur[/name_f]
[name_f]Orchid[/name_f]
[name_u]Snow[/name_u]
[name_f]Birdie[/name_f]
[name_u]Cricket[/name_u]
[name_f]Darling[/name_f]
[name_u]Berry[/name_u]
[name_f]Apricity[/name_f]
[name_u]Vision[/name_u]
[name_f]Windy[/name_f]
[name_f]Plum[/name_f]
[name_f]Wisteria[/name_f]
[name_u]Willow[/name_u]
[name_f]Valley[/name_f]
[name_f]Katniss[/name_f]
[name_f]Zinnia[/name_f]
[name_f]Lyra[/name_f]
unusual nickname name
[name_f]Marnie[/name_f]
[name_f]Hallie[/name_f]
[name_u]Duffy[/name_u], [name_f]Buffy[/name_f]
[name_u]Teddy[/name_u]
[name_f]Lulie[/name_f]
[name_f]Misti[/name_f]
[name_f]Alcie[/name_f]
[name_f]Liv[/name_f]
[name_u]Ocie[/name_u]
[name_f]Lulu[/name_f]
Mazzie
[name_f]Lindy[/name_f]
[name_u]Fran[/name_u]
[name_f]Mim[/name_f]
[name_f]Wendy[/name_f]
[name_f]Miffy[/name_f]
[name_u]Ozzy[/name_u]
[name_f]Lena[/name_f]
[name_f]Ro[/name_f]
[name_f]Avie[/name_f]
[name_f]Mitzi[/name_f]
[name_u]Lee[/name_u]
[name_u]Indy[/name_u]
double barreled name
I know a sister set of four sisters who have one double barrel name, one masculine name, and two classic feminine names between them. It’s a good balance for a good, eclectic set!
[name_f]Daisy[/name_f] [name_f]May[/name_f]
[name_f]Lucy[/name_f] [name_f]Claire[/name_f]
[name_f]Willa[/name_f] [name_f]Ruth[/name_f]
[name_f]Georgia[/name_f] [name_f]Bess[/name_f]
[name_f]Alice[/name_f] [name_u]Anne[/name_u]
[name_f]Nellie[/name_f] [name_f]Pearl[/name_f]
[name_u]Josie[/name_u] [name_f]Belle[/name_f]
[name_f]Thea[/name_f] [name_f]Claire[/name_f]
[name_f]Jane[/name_f] [name_f]Katherine[/name_f]
[name_f]Beth[/name_f] [name_f]Sarah[/name_f]
[name_f]Winnie[/name_f] [name_f]Kate[/name_f]
[name_f]Molly[/name_f] [name_f]May[/name_f]
[name_f]Charlotte[/name_f] [name_f]Claire[/name_f]
[name_f]Cora[/name_f] [name_u]Blythe[/name_u]
[name_f]Bridie[/name_f] [name_u]Joan[/name_u]
[name_f]Sadie[/name_f] [name_u]Wren[/name_u]
[name_u]Frankie[/name_u] [name_f]Belle[/name_f]
[name_f]Beulah[/name_f] [name_f]Bloom[/name_f]
[name_f]Mamie[/name_f] [name_u]Lu[/name_u]
[name_f]Zara[/name_f] [name_u]Lane[/name_u]
[name_f]Sally[/name_f] [name_f]Nell[/name_f]
[name_f]Franny[/name_f] [name_f]Kate[/name_f]
[name_f]Este[/name_f] [name_f]Rose[/name_f]
[name_u]Jude[/name_u] [name_f]Mary[/name_f]
non-English name
[name_f]Anya[/name_f]
[name_f]Niamh[/name_f]
[name_f]Juna[/name_f]
[name_f]Ophelie[/name_f]
[name_u]Roma[/name_u]
[name_f]Astrid[/name_f]
[name_f]Selah[/name_f]
[name_f]Anouk[/name_f]
[name_f]Elke[/name_f]
[name_f]Leonie[/name_f]
[name_f]Orla[/name_f]
Frigga
[name_f]Yara[/name_f]
[name_f]Mazarine[/name_f]
[name_f]Joia[/name_f]
[name_f]Sif[/name_f]
[name_f]Marya[/name_f]
[name_f]Tomine[/name_f]
[name_f]Austėja[/name_f]
[name_f]Katya[/name_f]
[name_u]Zola[/name_u]
[name_f]Shasta[/name_f]
[name_f]Ingrid[/name_f]
[name_f]Saoirse[/name_f]
[name_f]Zipporah[/name_f]
[name_f]Melina[/name_f]
[name_f]Thomasin[/name_f], [name_f]Thomasina[/name_f]
[name_f]Josepha[/name_f]
[name_f]Ewella[/name_f]
[name_f]Birgitta[/name_f]
[name_u]Camille[/name_u]
wildcard
[name_f]Twyla[/name_f]
[name_u]Leighton[/name_u]
[name_f]Morwenna[/name_f]
[name_f]Verity[/name_f]
[name_f]Concordia[/name_f]
[name_f]Wrenna[/name_f]
[name_f]Joycie[/name_f], [name_u]Joyce[/name_u]
[name_u]Phaedra[/name_u]
[name_f]Brynn[/name_f]
[name_f]Leocadia[/name_f]
[name_f]Zelda[/name_f]
[name_f]Myfanwy[/name_f]
[name_f]Vienna[/name_f]
[name_f]Enola[/name_f]
[name_f]Monday[/name_f]
What would you name ten siblings to these three girls: [name_u]Vision[/name_u] [name_f]Beulah[/name_f], [name_f]Clementine[/name_f] [name_f]Marilla[/name_f], and [name_u]Florence[/name_u] [name_f]Josephine[/name_f]?