Ok, all those Lego games are on the same engine.
They're still all different from each other.
They aren't, minor additions do not make it an entirely new game.
That's like saying each CoD game is not the same game because of a few re-skins, new maps and new weapons.
HUR THIS LEGO GAME HAS CHARACTER CREATUR ITS 100% DIFFERENT!!!!1!! HAO DO U EVEN SAY ITS THE SAME GAME??! They could of added a character creator in the previous games too but they didn't think of it until now.
Each game they put little thought into and they add a few minor additions to it. When they think of a new minor addition they implement it into the next game.
They are just adding onto the previous game! They could just spend an entire year coming up with a new concept but instead they use that time to recycle the previous game.