I've said this before, but the nice thing about the show not getting a third season is that we can go hog-wild with figuring out how The Great David Jenkins* would have written his way out of it, and never be proved wrong.
So far my favorite is "fuckery perpetrated by Izzy + some of the other crew, on Stede and Ed, because he thinks him being dead is what's needed for Ed to give up the Blackbeard role and let himself be properly happy with Stede."
Somewhere around episode two of the new season, we start getting a few glimpses of Izzy out of the corner of various POV characters' eyes, perhaps culminating in a full-on ghost-Izzy performance for the benefit of either Stede or one of the other crew who isn't in on it.
Meanwhile, it's becoming increasingly obvious that removing Izzy from the equation is not having the desired effect on Ed or Stede, and they're working their way toward some sort of plot-related doom. And Izzy, of course, is not making a clean break of it either, hence all the ghost sightings.
The ghost-Izzy scenario might go on for a couple of episodes, IDK, probably depends on budget considerations and Con's salary requirements, but we-the-audience have it confirmed for us that he's not really dead, an episode before the other characters do. Probably at the end of the episode, possibly in a context involving Izzy removing his ghost disguise while declaring, "Fuck this!"
Either way, he shows up to provide some small but crucial information or service at a critical point--like, "it's a leap year, boss," in the first season, but this time framed as being essential to Our Heroes' ability to regroup and succeed. Somewhere in there, he exposits about the whole pretend-to-be-dead-so-Ed-can-move-on plan, and then, emergency over, he makes ready to leave, saying he'll really go away this time, only to have both Ed and the crew ask him to stay, and then one or two other things happen, and somehow we get a happy ending. (Possibly Ed and Stede settling on land again, but this time set up as a relationship & life-course development for which they are ready, and Izzy going off to be First Mate to Captain Frenchie, IDK.)
(*Here I mean the guy we imagined/built up in our minds during the hiatus; dealer's choice how much he overlaps with the actual guy.)