If "Charlie" is a diminutive of "Charles," which means "free man," you could consider names like:
* Ελευθέριος (Eleftherios): This means "free" and is a more direct translation of the meaning of Charles.
* Αρίστος (Aristos): Means "best" or "excellent," which could evoke a similar sense of freedom and independence.
If you like the sound of "Charlie," you could look for Greek names with a similar sound, although there isn't a perfect match. You could even consider a name that evokes similar feelings like strong, cheerful etc. However, this would be more subjective.
Ultimately, the best "Greek" equivalent depends on your personal preference.