Answer:
I would try to use a gender-neutral term or maybe ask them.
Explanation:
I’m sure not many would take offense to being asked their pronouns or how to refer to them. If you’re concerned about asking that, I would just use a gender-neutral term or none at all.
Example: “Hello! Welcome to (Input plac).”
Another example: “How may I help you, friend?”
It may not be appropriate for some, but it could be beneficial
