The Korean movie you are likely referring to is the 2024 comedy Pilot, starring Jo Jung-suk.
It is a remake of the 2012 Swedish film Cockpit.
Plot: After a single, careless mistake costs him his high-flying career as a celebrity pilot,
Han Jung-woo (Jo Jung-suk) finds himself blacklisted by every airline.
In a last-ditch effort to get his job back, he undergoes a shocking transformation—he disguises himself as his younger sister,
Han Jung-mi (Han Seon-hwa), and successfully lands a new job as a female pilot.
