No, the humbucker in bridge position will definitely not make a Stratocaster sound like a Les Paul. The Les Paul have a totally different wood combination, pickup placement, neck scale, etc. All in all, it's a different kind of guitar.
A humbucker on a Stratocaster is only going to sound louder - a humbucker equipped strat. With the music style and way of playing Green Day has, I seriously doubt it will matter much at all what type of guitar they use.
The angling of the humbucker can have several explanations. One is to get the pole pieces to align better. Another is because of simplicity in mounting the pickup. A third would be because it could be seen as a weird gimmick.
Since the mumbucker is a more powerful pickup than the original single coil (plus, it's a twin coil pickup), you will not get the typical in-between sound of a standard strat. It's just a different flavor; go to a store and try out any HSS equipped start yourself.
And for sure, you're using way too much energy trying to figure out something mundane and unimportant detail like this.