There is a comparison to be made between the Sale trade (Moncada, Kopech) and one of your proposals for Degrom (Florial, Sheffield). One of the differences, though, is that Moncada already had success at Double A (a .900 OPS) before moving on to the White Sox. The jump from Single A to Double A is huge, some say it is a harder jump than Triple A to the Major Leagues. It is hard to place a ton of value on a raw prospect like Florial when he already has contact issues and he has never played an inning in Double A. I realize that Florial is an excellent prospect, but there is so much risk associated with him as well.
With that said, Kopech didn't have Double A experience when the White Sox acquired him, and thus took on tremendous risk with a raw prospect.
If I'm the Mets, and I'm trading Degrom, I'm looking for two top prospects who have had success at Double A or above. The Yankees aren't going to be the only team interested in Degrom.
Interestingly, if the Mets use the Sale trade as a model, that might be a disincentive to trade Degrom for Florial and Sheffield. That is, the Sale trade doesn't look all that great for the White Sox right now. Moncada is having problems at the major league level and the rawness of Kopech is catching up to him. Sure, he has a great fastball but he is walking too many batters. Again, the White Sox took on a big risk when they traded for Kopech, who didn't have any Double A experience. Thus, if the Mets use the Sale trade as a model, they will likely conclude that the White Sox didn't get enough for Sale, or didn't get enough proven talent in return for Sale, which is why the Mets should demand Andujar or no trade at all.
C.Frazier has experience at the upper levels, but again there is no room for Frazier on the Mets. Frazier would be blocked on the Mets more than he is blocked on the Yankees. The Mets are stuck with Cespedes and Bruce, and have young guys like Conforto, Nimmo, and maybe D.Smith if they move him off 1b.