I like it on a man only, and only as a nickname. When I was a child, my friend-who-lived-across-the-street's father was called
Red, though his real name was
John, because he had red hair. It's traditionally been a nickname for a man with red hair.
But I knew a
Red whom I really liked and who really liked me who did not have red hair. I assume
Red was a nickname in his case, too, but don't know what his real name was. I guess he gives me a soft spot for the name.
It could be a nickname for
Redmond.