That’s a question my blind client asks me and it sounds simple but you can’t currently do this with Alexa. That’s because , I think, Amazon has been a publisher not an operating system. Whereas Google is an operating system. That’s my theory. #
But you can do it via IFTTT ( love that website!) and OK Google by turning on this fix.
If you were a blind user you would need to have your screen reader on to make sure you know what you have written. No unwanted or rude messages can be sent unintentionally!