Cross Dressing / Gender Bender (Broad)

FL pretends to be a man for most of the drama. 

According to a shady fortune teller, the FL must pretend to be a boy until her 26th birthday or risk a terrible fate.

FL pretends to be a man for most of the drama.

Her mother forced her to dress as a boy since childhood to hide her identity / protect her. When she is kidnapped and sold to the palace to serve as eunuch she has to keep up the lie. 

FL pretends to be a man for most of the drama.

The FL has used her twin brother's identity since she was 12 to secure work as a scribe and ends up being sent to SKK (no women allowed) by the emperor.

FL pretends to be a man for most of the drama.

The ML mistakes the tomboyish FL for a boy and ends up hiring her to pretend to be his boyfriend so he can get out of blind dates, and then ends up hiring her to work as one of the attractive male staff members at his coffee shop.

FL pretends to be a man for most of the drama.

When the FL accidentally time travels to the past and ends up in the palace, she happens to grab mens clothing when trying to hide. She's mistaken for a man and ends up working with the Emperor.

The soul of one of the MLs ends up in a woman's body for most of the drama.

Gender bender. A modern day korean man's soul winds up in the body of a Joseon queen. 

FL pretends to be a man on occasion.

The FL sometimes dresses as a man while traveling with the ML or the army.

FL pretends to be a man for most of the drama.

FL takes her twin brother's place as crown prince.

FL pretends to be a man on occasion.

FL sometimes dresses as a man when providing medical care.

ML pretends to be a woman for a significant portion of the drama.

ML pretends to be a woman in order to infiltrate a female-only village while pursuing an assassin.

FL pretends to be a man on occasion. 

The FL wears mens' clothing and hides her face while on missions as a rebel sniper for the Righteous Army.

The FL pretends to be a man for a significant portion of the drama.

The FL spends a good portion of the drama pretending to be or at least dressed as a man (although they really don't put any effort into making her look less feminine). 

ML pretends to be a woman on occasion.

On at least four occasions the ML disguises himself as a girl or dresses as a girl to play a role. The fourth time is amazing.

FL pretends to be a man for most of the movie.

We all know the story. This version is closer to the legend than the disney adaptation - she spends years in the army and becomes a general. 

FL pretends to be a man for most of the drama.

FL pretends to be a boy in order to attend a boys-only military academy after her brother's untimely death. 

FL pretends to be a man for most of the drama.

The FL pretends to be a boy in order to audition for and join an all male idol group.

FL pretends to be a man for most of the drama.

When she's in the past the FL dresses as a foot soldier and passes for a man. While some characters figure out that she's a girl very quickly, others believe she's a man until almost the very end. 

FL pretends to be a man for most of the drama.

The FL takes her twin brother's place when he is temporarily unable to take a big-break opportunity to join a male idol group.

FL pretends to be a man for most of the drama.

The FL pretends to be a boy in order to enrol at the all-boys boarding school where her idol, a student athlete / high jumper, is struggling.

FL pretends to be a man on occasion. 

FL sometimes dresses as a man.

FL pretends to be a man on occasion. 

The FL dresses as a man while working as a bandit.

FL pretends to be a man for a significant portion of the drama.

The FL is a swordsman and normally dresses as a man, although all the people that are close to her know she's a woman so it's not a major part of the plot.

FL pretends to be a man on occasion.

The ML and FL meet as children. When they first meet again, the FL is dressed as a man while traveling.

FL pretends to be a man for a significant portion of the drama.

The FL dresses as a man in order to take her niece to a father-daughter art event and ends up getting hired to a big gaming company.

?

When the FL serves at the ML's side she spends much of her time disguised as a man and even has several female admirers. 

Dropped

FL pretends to be a man for most of her life, but not for most of the drama.

The FL is a general and pretended to be a man for many years. The ML is often mistaken for a woman from a distance. 

ML dresses as a woman for most of the drama.

ML and FL swap bodies / souls. 

ML mistakes the FL for a guy for most of the drama.

ML and FL swap bodies / souls.

FL pretended to be a man for most of her life.

ML and FL both pretend to be the opposite gender at times later in the drama.