Here are a few options:
* Dorothée: This is the closest you'll get to a common French name with a similar sound.
* Darlene: You can simply use the English name "Darlene". It's becoming increasingly common to use English names in France.
* Daria: This is a Russian name that sounds similar and is sometimes used in French.
Ultimately, the best way to say "Darlene" in French depends on the context and your preference.