Is it true that Mulan joined the army? How does it work technically? If it's fake, why is there a Mulan Ancestral Hall or something? Thank god, help me.

Answer you with a joke. Someone watched the TV series Mulan Joining the Army and angrily said to the person in charge of the office, "This historical event is so fake that even a fool can see that Mulan is a woman. But none of the police officers who ate and slept with her noticed. How is this possible? " The boss glanced at a man and said slowly, "If you were that officer, would you realize it?" "Of course." Someone said, "A woman who lives next to her can detect it with her sixth sense." "You find a female soldier to get along with you day and night, will you be silent?" Follow-up: Is it a hidden rule?