So, we know the following players have a place on the roster when healthy:
Grandal, Collins, Abreu, Garcia, Anderson, Moncada, Jimenez, Robert, Engel, Vaughn
That leaves three spots. How many of Mercedes, Mendick, Lamb, Hamilton, Goodwin, Eaton do you keep? If you're going to get an outfielder, it has to be a lefty and has to be certain to outproduce all of Hamilton, Lamb, Goodwin and Eaton to justify getting rid of all of them. If you're going to get an infielder, it has to outproduce a Mendick/Leury platoon. I think the IF option is more likely. I don't see an OF acquisition barring further injury. One of Lamb/Hamilton/Goodwin/Eaton will make a viable platoon partner for Engel, and a trade for a 2B is made, then Leury also becomes an OF option.
On the pitching side, the five starters plus Hendriks, Bummer, Crochet, Kopech and Marshall are not going anywhere. That leaves Heuer, Fry, Foster, Ruiz, Burr for three spots. I could see a bullpen acquisition to fill one of the three remaining spots.
Hahn is technically correct in that it's too soon to know if the Sox will be "buyers" without knowing the price, but it's not too soon to know that the Sox will at least be "shoppers" for a 2B and RP.