I think it was the prolific, consistently awesome +Andrew Shields who called for an art skill in Blades in the Dark, something to represent a scoundrel creating any work of art, just as handle allows one to drive any vehicle. (Andrew if I'm wrong on this, sorry to single you out.) For once I have to disagree.
(Edit: Ha I was totally wrong about this. Andrew linked to his post, which is basically the same thing I'm blathering on about here. I am somewhat embarrassed to misrepresent him, but, at least I can call myself out here.)
If you listen to the Jank Cast's Apocalypse World campaign, Black Diamond, there's a neat part where one of the characters, Frost, a Skinner, wants to play a song on his fiddle. Perhaps this requires context. There's this angry, murderous mob, snarling at someone the characters want alive. Some PCs are gearing up for a fight, some are gearing up for the fight's fallout. Frost's player leaps out of silence and declares he is playing a tune on his fiddle, about how wonderful and murderous the black diamondoids are. How brave, how martial, how they all need to go have a good shag.
The MC basically tells Frost's player, 'OK, if you're playing a song that's good, that can just happen. Are you trying to do something with this song? Sway the crowd or something?' And thereby we get to the meat of what is going on. Apocalypse World is not Basses and Banjos; if a character wants to say his gunlugger can play guitar, we can all just nod our heads and say 'alright.' But if the character is trying to seduce people or drum up a mob or psychically invade people's minds whilst singing a tune, there's rules and moves for that.
I think Blades in the Dark can handle things in a similar way. Fundamentally, the game is about rogues on jobs, or rogues dealing with the results and side effects of their work. It also already models downtime activity, where the PCs investigate things or work on long-term projects. I'd say we can dice up art along these lines. If the PCs are using their art to sway people, and their art can be wheeled out or sung to those people, the player gets to roll Sway. If they're trying to convince an art critic that their art is Real Art and not Dross Shite, ask the player what they think they ought to roll. It'll vary - I could see Cipher working (the art references other art in subtle, knowing ways), Deceive (obviously), Command (the force of personality burning through the art terrifies the critic), Sway, Invoke (the art twists with the dripping influence of the Void). Deceive is good if the player doesn't believe his character's art is authentic (or the art isn't concerned with such), sway works if the art legitimately climbs on the pedestal of Actual Art.
For downtime, a long-term clock to 'make art' could get filled in a number of ways, and one result of a 4-5 rolled could be to force the player from one skillset to another, one approach to another. The clock isn't always necessarily filled in the same way. Your Rhyme of the Ancient Mariner can't just be done from your character's ability to sail (Handle) - maybe you need to Invoke something, maybe you need to go down the bad side of town and indulge in some Mayhem.
For long-term work, it's very important for the GM and the player to know and agree to what it means when the clock is full. A successful showing or book deal, recognition or acclaim, a legitimate front for the players to hide behind. You can make art for art's sake, of course, but that's going to make the clock rather anticlimactic.
Art may also be an acceptable Vice, if the player if fine with using it to clear stress and not really getting much out of it, other than overindulgence, trouble, and occasionally useful rumors. For many real-life artists I imagine art was a mix of all these things - useful to the artist and using the artist by turns.