I first threw out the insane Robert, Cease, and Graveman package, but my point remains that Chicago continues to have the most SP options available, so if you are willing to invest in Robert (and I absolutely would be), it makes sense to look at big packages that include pitching.
To me, this is the clear scenario where you give up Gilbert, Meyers, and another OF prospect or two, plus Lee, Leon, Ullola OR Arreghetti (not both), and some filler plus 40 man relief such as Perez.
Robert gives you 4.5 years of elite defense and offense in CF which is a full window stretch. If you keep Chas, you can move him to LF and still have room to work in Brantley if he returns in effective fashion. It is the one place we can really upgrade without creating a roster/lineup crunch.
Cease gives you another impact playoff rotation arm with immense upside and innings eating yo help get our bullpen fresh again. To me, we need high upside contigency in case Javier isn't himself come postseason.
Alternatively, I have kept an eye on Verdugo and wondered if Paxton might be a package option as he has been effective since coming off the IL. I have always been a fan of his ability since his SEA days.
The Yankees/Chas thing makes for interesting headlines, but there is NOTHING that there that we would want. The Yankees are more desperate for offensive upgrade than we are.