How exactly is Puig "extremely overrated"? All anyone can really go by is what he did in spring training, minors, and since his call up. Not to get too hyperbolic, but he's been nothing short of outstanding.
That's not to say I'm necessarily in favor of trading Chapman, but if there actually were a chance to get Puig for Chapman + prospect, I would do it every day of the week and twice on Sunday. Sure the rest of the league might get the book on Puig and he proves to be a flash in the pan, but that's a risk I would take.
Now, you want an overrated Cuban? Hint: Plays a terrible LF for the A's, K's in his sleep, and is more fragile than a China doll.