Did you guys notice one thing about their accent? Philip is Korean-American so whenever he speaks in Korean, you will feel a little bit American accent, soran is Chinese character so whenever she speaks in Korean that's Chinese accent ( Infront of sato), lee gakyung is Korean so whenever she speaks in English there's Korean accent and sato shinchi is japanese so whenever he speaks in Korea there's japanese accent. (All the actors are Korean but they learned other languages)
https://youtu.be/WXYQMgpr2Gw?si=FW72i7AF43aDrZ4q
(All the actors are Korean but they learned other languages)