This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development is uncertain. The modern form combines 女 (woman) with 皇 (emperor), but the original meaning and component relationship are unclear.
The left side is a woman 女, and the right side is an emperor 皇. Without a clear meaning, imagine a woman standing beside an emperor, but the significance is unknown.
For コウ, picture a woman 女 bowing to the emperor 皇 in a grand court: court -> コウ, and the scene helps recall the reading.