I would be shocked if we can actually land the right deal for Kessel. It would have to be a star for star kind of deal imo. You simply don't win stars for parts deals in the short term. And we aren't making trades for the long term.
This isn't completely true. You can win starts for parts deals very quickly... but only if the star is not as vital as people thought and in making the deal, it lets you cater to the needs of your other stars and internal guys step up. Ref: Duchene, O'Reilly.
Is this applicable to Kessel? Mainly no. We don't have the internal pieces (Sprong not working out has put a dampener on this), he's not a dressing room problem or anything. And he's pretty important.
But there's a certain amount of yes in that Geno wanders the desert when it comes to linemates, either trying to make him and Kessel work (I'd say a quarter of the time its as good as it gets and the rest of the time its deeply flawed) or making do because we spent our stuff when it comes to star wingers there. This is amplified by the fact that Hornqvist is a death or glory fit with Geno as well. If you got a part that really fitted with Geno... I think you win the trade.
I think that's the only way the Kessel for parts trade works right now (unless you already got your replacement in free agency). Or Kessel for lesser player and 1st, as Sidney mentions. But it's in my mind.
edit: p.s. I have to disagree with ColePens about Kessel fitting with our identity. I think its quite conspicuous that he's really not a Sully type player. That he does such good work here is testament to his talent, but I'm pretty sure other systems would get more out of him.