Honestly I wouldn’t think any of them have the emphasis on Leah.
To me these spellings would be pronounced as follows: Karleah - Carly Kayleah - Kayleigh Karlia - Car-lee-a / Carly-a Kaliya - Ca-lee-a So the bottom two work best if you want a "Leah" sound. I like the sound of Kaliya best.
Kahlia?
The first option is my name! I will tell you a lot of people mispronounce it as Carly. Which irritates me a little bit because LEAH is pronounced lee-uh. I honestly hated my name when I was a kid because people mispronounced it so often, but now that I’m an adult, I absolutely love it because of how unique it is, and I get compliments on it all the time.
“Karleia” sounds more like that to me x
I know a Carlia so Karlia would be more natural
Kallia Kaliah Kalia Kaleah
I like just Karly/Carly 😊