My great aunt was Sylvia Belle which is pretty fab, maybe Sylvie Belle would be more contemporary…
Belle goes with most names but because it’s visually strong, I think the first name needs some hefty letters (like the Y and V in Sylvia) and a bit of length.
Eg:
Harriet
Verity
Ursula
Tabitha
Louisa
Delilah
Bryony
Tallulah
Leonora
Valerie
Coralie
Dorothy
Seraphina
Georgiana
Clementine
Theodora
Penelope
Hermione
Josephine
Hope this helps!