While it's highly unlikely, no matter their situation that the Penguins would trade the 2005 first-overall pick after all he's accomplished, stranger things have certainly happened.
18 years into his career, Crosby has accomplished all that you can as a member of the Penguins, and while trades like this are fun, most teams are too sentimental about their legends, and that's likely the case here.
On top of leading Pittsburgh to three Stanley Cups as captain, Crosby has put up some incredible numbers, playing in 1,190 games in his career with 550 goals and 952 assists for 1,502 points, but still, it's fun to speculate about him potentially finding another contender to join.