vijayjohn wrote:In what language(s)?
English, French, Spanish and Portuguese, but also stuff in other languages is ok as long as there is a translation in at least one of the four above-mentioned languages.
My favourite genres are sci-fi, dystopian, fantasy and horror, but I accept also other genres.
Well, for French, there's always Jules Verne. For Spanish, there's Jorge Luis Borges and Julio Cortázar. There's also a Peruvian folklorist named Ricardo Palma who IIRC included some rather unrealistic stories, although my memory of that is very hazy now. I don't think I've ever read anything by Horacio Quiroga, but you might find his stories interesting, too, if you're not already more familiar with him than I am.
I'm not sure what to recommend for Portuguese since I haven't read anything in it really.
And then for English, I can recommend at least Ray Bradbury, Kurt Vonnegut, Joan Aiden, and Stephen Vincent Benét. (That's all that I can think of right now, but I'll let you know if I think of anything else and you want any other recommendations).
For other languages (with translations into English), I'd like to mention Zhang Jie and Hwang Sunwon, who have both written great short stories even though I'm not sure any of them are really up your alley.
There's also a great short story by R. K. Narayan called "Like the Sun," which is in English originally. That's probably not really what you're interested in, either, but I thought I'd mention it because out of the many short stories he's written, this is the only one I've read that's actually good.