Ooo, let a non-native speaker join in!
Using literally when meaning actually.
beggar belief/beggar’s belief - very weird. Why not, “it begs belief”?
Also, compared to other languages, English speech references foot/feet and parts theoref way more often than I’ve seen it in other languages. It’s more apparent in novels, where it’s part of descriptive language. Makes me think, why not use legs once in a while (as other languages do). Poor hands nary get a mention by comparison.
Using Man/man to mean Human. Mankind vs. Humanity. Especially annoying when used in syfy settings, like a future Earth government. Makes me think sarcastically, gee, good thing women aren’t part of this.
Particularly in Star Trek novels. You know Klingons, the Groundskeepers, Founders? They don’t mingle with Humans, they only meet humans. Urgh, be consistent, darn it.
Good luck! In my native language, you can wish luck or success, and my maths teacher once explained in detail why success is better. But in English you can only say “Good luck!” or use a stiles phrase like, “I wish you success.”