Magical Girls in the Second Mundial War

I'm planning a fanfic about a group of magical girls set in the Precure universe. Because of certain facts throughout the franchise (that there have been Precure groups all over the world, not just in Japan), I want to create a magical girl group consisting of a Japanese girl, a Chinese girl, a Korean girl, a French girl, and an American girl.

Most of them didn't know each other until they were kidnapped by the Japanese army, and... And if you know about World War II, you know what happened to kidnapped women... Yes...

Well, the girls managed to escape and were found by a Japanese woman who, for reasons I'd rather not reveal since it's part of the fanfic's plot, disagrees with what her country is doing and hides them in her house. (There's also a reason why a woman in Japan would have a house to herself; it's a complex matter.)

Thanks to the magical item (the thing that transforms them), they can understand each other, but misunderstandings still arise due to their cultural differences.

What misunderstandings could happen between these girls? I mean casual gestures, table manners, and things like that. Not about "submission" or anything like that (I made the mistake of asking ChatGpt first).

I'd also like to ask about movies from that era to learn more about the context of each country and how people lived their daily lives there.

I'm mainly looking for movies about China, Korea, and Indochina Francesa (present-day Vietnam) because there's a character who's originally from there (and who's a villain seeking revenge for the annexation of her country and its people). Thank you so much if you read all of this.