1 Corinthians 16:13 “Watch! Stand firm in the faith! Be courageous! Be strong!”
In the Greek, “Be courageous” has the meaning “act manly” or “behave as men”.
Deuteronomy 22:5 “A woman shall not wear men’s clothing, neither shall a man put on women’s clothing; for whoever does these things is an abomination to Yahweh your God.”
As you can see Scripture tells us that men need to behave like men. Men should not try to be or be like women. Women should not try to be or be like men. In today’s world there are many clothing items that are shared between the sexes. So the admonition is to avoid those items that are distinctly of the opposite sex.