Congratulations 
I think naming in general is really challenging and I can imagine naming multiple girls would be hard. As a result I completely understand why you’re finding naming your third baby tricky. Also you’ve got tons of postpartum hormones running through your system which would make the naming process even more challenging. Still I just want to remind you that you have time so don’t feel any pressure you will find that perfect choice.
Looking at your list I absolutely love [name_f]Flora[/name_f] 
For me [name_f]Flora[/name_f] is absolutely stunning such a sweet, bright, charming cottagecore choice that feels ever so timeless with Clair3 and Elois3. [name_f]Flora[/name_f] is a beautiful name really gorgeous she just appeals to me so much! [name_f]My[/name_f] second favourite is [name_f]Dahlia[/name_f] she’s a spunky floral choice that I think feels fun, a little unexpected with your girls. So those are my favourite but I am a sucker for nature names.
Looking at your favourite [name_f]Zoe[/name_f] I think she’s a great choice. [name_f]Zoe[/name_f] is classic, elegant, bright and sparkly with a pan European feel. I think [name_f]Zoe[/name_f] works very well with Clair3 & Elois3 they are all familiar classics with that ‘e’ ending which makes them feel very stylistically in keeping with each other. Completely understand why this name is so high on your list. I also think [name_f]Beatrice[/name_f] is a timeless choice, with a lovely meaning and has that e ending.
No wonder you’re struggling you’ve got a lovely list so it must be hard to narrow it down!
You’ve had lots of lovely suggestions so count any repeats as me being in agreement with the berries
Clair3, Elois3 and…
Juliet/Juliette
[name_f]Amelie[/name_f]
[name_f]Felicity[/name_f]
[name_f]Blythe[/name_f]
[name_f]Olive[/name_f]
[name_f]Leonie[/name_f]
[name_f]Noemi[/name_f]
[name_f]Selene[/name_f]
[name_f]Marianne[/name_f]
[name_f]Rosalie[/name_f]
[name_f]Isabelle[/name_f]
[name_f]Violet[/name_f]
[name_f]Heidi[/name_f]
[name_f]Ingrid[/name_f]
[name_f]Daphne[/name_f]
[name_f]Hope[/name_f] this helps