If you join any games and changing the key that converts from English to Korean (called Korean/English key), the character can’t controllable.
It appears ONLY in-game, studio doesn’t appear this bug.
in-game:
https://youtu.be/iYboCgXeuJU
in studio:
https://youtu.be/WP8p75iQYYs
my windows spec is Windows 10 (1909) OS build 18363.1256.