Closest to the sound:
* Ραχέλ (Rachél): This is the most phonetically similar, using the Greek letters for "R," "a," "ch," "e," and "l."
Meaning-based:
* Ρήγνη (Rhēgne): This means "queen" and could be a beautiful alternative with a similar sound.
* Αρετή (Aretē): This means "virtue" or "excellence" and could be appropriate if you want to emphasize Rachel's good qualities.
* Ελισάβετ (Elisávet): This is the Greek spelling of Elizabeth, which shares the similar sound of "El" and has the meaning of "my God is abundance."
Ultimately, the best spelling depends on your preference and the context.