What is the homonym for guys?

There is no direct homonym for "guys" in the sense of a word that sounds exactly the same but has a different meaning.

However, "guise" is a homophone, meaning it's pronounced the same but spelled differently. "Guise" refers to an outward appearance or manner of dress, often used to disguise one's true identity.

Here's an example:

* Guys: "Hey guys, let's go to the park."

* Guise: "He entered the room in the guise of a wealthy businessman."