There is cross-dresser looking for perfume inside the mall where you are working As the
sales clerk how will you address the customer
properly to avoid discrimination?

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

1 - shakespeare

2 - stephen king

3 - stephenie meyer

4 - seiichi morimura

5 - sabrina elkins

6 - sally cheney

7 - samantha hunter

8 - shelley bates

9 - sue civil-brown

10 - sylvie kurtz