"Could you recommend some wine" (some referring not to quantity, but to some type of wine) sounds more natural to me. Should definitely be added to the correct answers.
Agreed. Both are correct.
I disagree, this is fine the way it is. Some wine sounds unnatural to me, and feels like you're taking the partitive context too literally.
Could it be recommend wine (without a or some)?
What is difference between voisitko and voisitteko as to when one or other is appropriate
Voisitko is second person, singular (sinä), voisitteko is second person plural (te) or also a polite/formal way to address someone (singular)
"A wine" is perfectly good American English, especially in the context of recommending one.
"A wine." Is also fine in standard British English. However the Finnish viiniä is partitive so would that not suggest "some wine." as an answer?
No, because partitive doesn't literally mean "some". It is just a vessel of understanding for English speakers.