I am not a native English speaker but it is my understanding that handsome can be used with things, meaning beautiful or also elegant
I am a native English speaker (both New England and West Coast dialects) and "handsome" could be used, applying it as a near-synonym to "elegant," but it feels very formal, and I can't say I've ever actually heard it used to describe a language. That said, I definitely have heard "That was a handsome turn of phrase" used to describe a particularly elegant use of language. Seeing it used here made my eyebrows go up (in reflexive skepticism), but after a moment of squinting at it I decided it was possible, albeit improbable.
Without being harsh, you must be fairly isolated dialectually. If you win a lawsuit, you might get a "handsome" settlement. If you're looking for a new flat, the rental costs may be too "handsome" in some neighborhoods. It's actually quite common to use handsome in UK English describing monetary value.
Friendly reminder that downvoting a sentence discussion is not a good idea! When a sentence's tally sits at anywhere below zero, the sentence cannot be searched for any longer; and at -5, it vanishes from the Sentence tab in the forum. Together, this means that the people who need to find these sentences to fix them, answer questions, etc. cannot find them any longer (except through the course itself which is very time consuming!), and thus nothing can be resolved.
So please, don't downvote sentence discussions!
Volgav vitsenanieff nivya kevach varatsach.
One of the definitions of "handsome" in the Oxford Shorter English Dictionary is "easy to use." Another is "handy".
It seems that languages can be handsome. I am learning other languages to better understand my own. As Rabbie Burns said, "O wad some power the giftie gie us, To see oursels as others see us."
It seems the answer is no. My friend's wife who is Finnish (and her first language is Finnish), says she would never use komea to describe a language. It's about the same as handsome in English and stilig in Swedish. You would understand the sentence but it's not the common way of expressing yourself.
I'm convinced that that the ones here saying that it's some kind of play with words are right (korea and komea looking alike). That's not very pedagogic from the course constructors though, and it just takes a lot of time to sort out for us confused users.