I don't know if it has been translated but I would recommend "Die Känguru Chroniken".

It's a humourous book about a communist kangaroo moving in with a comedian. Many great jokes have established themselves in left leaning german meme culture as a result.

The book mostly has standalone chapters, but the sequels have more of a narrative throuline.

So I'm English, but I know German. The book "Der Buchspazierer" is really good book that I've discovered recently. It literally means "the book-walker," but the official English translation is "The door to door bookstore."

They're also making it into a movie in Germany, so you could wait til the movie comes out if you want.

Anything by Gabriel García Márquez. Creepy haunting tales, dramatic epics, magical settings. Also, read Jorge Luis Borges, some of the most creative and mind twisting short tales and narratives. “Casas muertas” by Miguel Otero Silva beautifully narrates the curse of oil in Venezuelan society and the mar left by imperialism in Latin American societies. Isabel Allende takes your breath away. And of course any short tale by Julio Cortázar.

A great series is the german "Tatortreiniger" which translates to something like "crime scene cleaner". I'd describe it as a small scale theatre like series, each episode playing inside a house or a few rooms, with a few characters. The main character usually has to clean up a crime scene and is confronted with the other residents of the building. It has a special kind of humor, mostly transported by really strange everyday situations.

I am American, but my favorite author is Argentinian: Samanta Schweblin. Four out of five of her works have been translated to English but you can easily find the original Spanish texts. Distancia de rescate (Fever Dream), Kentukis (Little Eyes), Siete casas vacías (Seven Empty Houses), and Pájaros en la boca y otros cuentos (Mouthful of Birds) are the ones I’ve read (in English) and can strongly recommend. Her books are often disturbing in some way, with stream of consciousness/hallucinatory narration. She dives into little moments in people’s lives and explores their humanity.

Tropa de elite, bacurau and Bingo: o rei das manhãs comes to mind. If you get away from comedy, our most common genre, you get pretty much a good movie from Brazil.

(Czech)
Ludvík Vaculík: Morčata/The Guinea Pigs. It's about a man, who rears and mistreats guinea pigs to compensate for his own bridled life.
Any play by Václav Havel, if you're into absurd drama.
From newer authors, Anna Cima: Probudím se na Šibuji/I Wake Up in Shibuya, magic-realistic story of czech japanist, who left her soul (literally) in Japan.

Oh, I've just read you want untranslated works, I cannot find such a book I'd find recomendable enough, but try watching some Cimrmans, you'll find them at YouTube.

I'm an English speaker, but I loved the Metro series of books (which are in Russian). Had a helluva time finding translations, though. The books are way more interesting than the games with a much more crazy twist in the first one. I thought they would just help with context, but the games deviate a lot from the books.

Other Russian books I've read include Roadside Picnic and The Wishgranter (because of STALKER).

Chinese is not my speaking language but Wuxia novels (ancients Chinese kung-fu novels) by Jin Yong are classics in Asia. They got translated to many languages including English iirc.

https://en.m.wikipedia.org/wiki/Jin_Yong

The five agreements from Mexican Author. It is a really nice book.

There's Oorlogswinter (Winter in Wartime) by Jan Terlouw. It tells the story of a teenager's time during the German occupation. Specifically, how he survives the winter of 44/45, which is commonly known as the "Hunger Winter." It was written for young teens, so it's not super challenging, but it's still an interesting story written by someone who's lived through it himself.

For movies, there's the Resistance Banker. It's loosely based on true events (as it's somewhat dramatized for the screen). It's about the brothers Van Hall, who played a major role in financing the Dutch resistance.

Then, for something not WW2 related, there's a bizarre comedy series called Rundfunk. I think it can be found with subtitles on youtube, but I'm not sure about the quality. It's about two guys in high school who are, well, kinda losers tbh, and the other bizarre characters in and around the school. If you do end up watching it, I want to say two things: 1) It was broadcasted on national television, and it was less censored there than on youtube, and 2) it was partially made using taxpayer money.

I recommend El Chavo del Ocho (imdb link), it's a Mexican show that is very popular here in Brazil

I highly recommend "Das Boot" by Lothar-Günther Buchheim

If I'm being honest, there isn't a single thing I've read in my pre-English language. I learned English and then learned how to read and it just stuck. I don't even know if any notable works exist in the language.