Baby Name Poll Results

Kai a twin brother? I adore Kenna, Ayla and Willa. Since big sister has a K name as well in her name, I would go with a different letter than K for a girl. Ayla fits nicely with Kai and Lexi-Koa.

Lexi-Koa +

Haven
Rue
Aylin
Bree
Lana
Arwen
Lila/Lyla
Ember
Alaia
Audra
Indie/Indy
Zara

I prefer the spelling Kai over Khai.
Of the other names you listed I really like Willa but agree with you that none of the ones listed in your description flow really well with Kai as a whole.
What about changing Kai to Kaian, Kaianne, etc... but calling her Kai? I think that would greatly increase the flow Kaiann Willa.

Sorry I didn't explain, it would be like a hyphenated name ___ - Kai
We don't know what we're having but I like Kai for a girl and Kal for a boy
I love Ember! I like Zara & Indie too but I'm not sure Indie-Kai sound good together
I also like Alaia, which remained me that I also like Amaia
I'm not sure… I feel like maybe I should save Kai for a boy and use something else for a girl… I like Noa too, maybe Indie-Noa

Am I understanding correctly that you want to use Kai/Khai for a girl and you want it to be a double name like Lexi-Koa?
If so I think Ayla-Kai totally works.
I'm assuming your pronouncing that with a long A.Like Kayla without the K.
If so that's definitely my favorite!

Oh, okay! Understood now. I think Kai works either way, but I do prefer it on a boy. Indie-Noa would be darling, but I think that Noa is too close to Koa. If you call them by the full name, it would get confusing imo. Indie-Kaye maybe? Flows a bit better than Indie-Kai. Alaia-Kai and Ember-Kai work well.

Lexi-Koa +

Ivy-Blair
Romy-Kai
Mila-Quinn
Poppy-Kai
Eva-Raine
Ember-Sloan
Molly-Rue
Haven-Roe
Eden-Bay
Darby-Lux
Vida-Sage
Etta-Leigh

Axel-Kai
Ozzy-Kai
Kai-Evan
Tao-Kai
Finley-Kai
Owen-Kai
Theo-Kai
Kai-Ronan
Anders-Kai
Britton-Kai
Kai-Merit

I think Willa-Kai works. Indie-Noa does too. I admit Kai and Noa are names I am not a fan of. I do not like Ember either. They are dying ashes or the end sounds of the fall months. Neither is pleasing.

Maybe?
Zara-Lou
Alaia-Ivy
Amaia-Rae
Indie-Sage

If you can't tell if a names "goes with" another name or not, most likely they don't outright clash so you're fine.

Lexi Koa and Isla Kai💕