The message is telegraphed from birth. Infant girls are swaddled in pink. Boys in blue. Girls wear skirts. Boys pants. The clichés fall easily from our lips. “Clothes make the man,” we say; “who wears the pants,” signals dominance. “A basic purpose of costume is to distinguish men from women,” Alison Lurie writes in “The Language of Clothes.” Dress, traditionally, is the membership card of gender.

In an era of gender fluidity, all bets are off. As the binary of male/female falls by the wayside, fashion follows suit—and has done so periodically since 1507-1458 BCE, when the Egyptian Queen Hatshepsut ruled Egypt as pharaoh wearing male regalia and a false beard. More recently, the Italian designer Alessandro