I've posted a few in threads on the Metal forum with photos. You can search my posts for them. I don't specifically watch K or J shows so I only know a few.
Fumino Kimura in Ishi no Mayu with a large Seiko, Yoona from Girls' Generation in Cinderella Man wears a few, Yvonne Lim in Your Hand in Mine (Chinese/Malaysian not K/J) wears at least 3 different large watches. This movie which I don't remember the translated title:
https://ok.ru/video/7317159676545 - she wears a knock-off Sub and even has a close-up shot when she checks the time.
One that I did not post yet is Konna Koi no Hanashi, the actress wears a Submariner-style watch. (could be Seiko, hard to tell). The show is pretty old, but you can watch it in full in low quality on Dailymotion.
https://www.dailymotion.com/video/xqazcj
I also have this note in a file with no photos, maybe you can track this down and post something: Korean drama 2013 The Scandal - 스캔들
Kim Gyu-ri 김규리 plays Jang Joo-ha 장주하
midsize silver left wrist + handcuffs 20130714
other variety of watches
