Hong Kong 1941 with Chow Yun-fat an unflinching look at Japanese occupation of then-colony
1984 Leong Po-chih film with Chow Yun-fat as one of a trio of friends stays character driven while showing Japanese atrocities, expert says

Directed by Leong Po-chih (or Leung Po-chi) in 1984, Hong Kong 1941 is an unflinching look at the horrors of the Japanese invasion of Hong Kong.
Here we discuss it with film historian Frank Djeng, who provided the commentary for the film’s Eureka Entertainment Blu-ray release.
Hong Kong 1941 really gets to grips with what happened to ordinary people during the Japanese invasion, doesn’t it?
Yes. Very few Hong Kong films have dealt with war seriously, and only a few, like Love in a Fallen City, have been made involving the Japanese invasion of Hong Kong.
Hong Kong 1941 is very character driven – there’s a love triangle, which has two guys loving the same girl, in the first third. Then the Japanese invasion erupts into the story, with all the atrocities that it brings.