"Nothing is easy."
Translation:कुछ आसान नहीं है।
I think it's actually the English that's idiomatic and confuses it. If you remove the negation, कुछ आसान है, there is an easy thing; नहीं है there isn't - ergo nothing is easy.
The phrase कुछ नहीं alone does mean 'nothing', but I suppose in Hindi, as in literally-taken English, using this order is saying that the absence of a thing is itself easy.
This probably arises because in English 'nothing' is a contraction of 'not one thing'; whereas कुछ नहीं is two words, and just plain negation, so as always नहीं comes just before the verb है।
Yes, in less literal English we have 'Something is not easy', and 'Nothing is easy'. They are logical equivalents of course, but colloquially subtly different, at least in emphasis.
I'm curious if Hindi lacks the (subtle) distinction here, or if it's just achieved differently, with tone of voice or timing or something?
कुछ नहिं at least when not in more of a sentence does mean 'nothing'; so I wonder if it can be achieved by playing with the word order?
That's right; the difference is conveyed by emphasis (tonally or with additional words), pauses or altered syntax. Context greatly aids the discernment. Here are some examples where कुछ indicates "something", not "nothing":
कुछ तो आसान नहीं है। - Something is not easy. (तो makes the preceding word the topic of the sentence.)
कुछ --pause-- आसान नहीं है। Something isn't easy. (Imagine a suspicious tone.)
कुछ है जो आसान नहीं है। - There is something that isn't easy.
कुछ चीज़ें आसान नहीं हैं। - Some things are not easy. (Introducing a noun (here चीज़ें) so कुछ acts an adjective.)