I think if there is a J15B, it will be a more strike oriented modification as it shifts role from primarily air superiority with secondary strike to primarily strike with secondary air superiority as the future 5th gen carrier fighter is selected and developed.
As such, I would not really expect much in the way of significant structural modifications/changes for the J15, certainly nothing like the Silent Eagle as that model suggests. The only structural mods I expect are structural reinforcement to allow it to hang more heavy ordinance and strengthened front landing gear and supports for catapult launch.