It's important to note that "Alexa" is the name of Amazon's voice assistant.
If you're looking for a Spanish equivalent to describe a voice assistant, you could use:
* Asistente de voz: This literally translates to "voice assistant".
* Asistente virtual: This translates to "virtual assistant".
However, "Alexa" is simply a proper noun and is used in Spanish as the name of the device or service.