I like [name_f]Rose[/name_f] the best out of your picks
[name_f]Clara[/name_f] and [name_f]Leah[/name_f]
[name_f]Clara[/name_f] and [name_f]Alice[/name_f]
[name_f]Clara[/name_f] and [name_f]Freya[/name_f]
[name_f]Clara[/name_f] and [name_f]Elisa[/name_f] (or Elise)
[name_f]Clara[/name_f] and [name_f]Thea[/name_f]
[name_f]Clara[/name_f] and [name_f]Edith[/name_f]
[name_f]Clara[/name_f] and [name_f]Ada[/name_f] (or Adah)
I also like [name_u]Clare[/name_u] and [name_f]Alice[/name_f] because of the e but if you are set on [name_f]Clara[/name_f] then I still think it goes really well with [name_f]Alice[/name_f].