I doubt changes in BW2 games are going to affect that much Iris in anime.
Granted we can't know for sure if in anime there exists some alternate way to become champion without having to collect badges and enter regional league first, like its case with gym or E4 position with there existing more than one way to become one.
While she is champion in new games and showed to be prodigy trainer in anime(at much younger age than Ash scoring 99 wins with only Excadrill) with both Drayden and Cynthia recognizing potential in her to become very strong trainer one day, at this point Iris is still far too young to cut for champion material.
She is still fairly unpolished in her skills, Axew has a lot more growing to do before he evolves and reach ultimate stage, and Iris herself didn't managed to connect with dragon types to such degree to fully understand their feelings and hearts, like dragon masters do. In strength and battling abilities she has a lot more to learn too being far from level of strongest dragon trainers out there, such as Drayden or Lance.
At best i could see her due to changes in BW2 games eventually becoming Drayden, Cynthia or some other elite trainer apprentice training under their care and learning new things, before she becomes ready to take on E4 challenge and becomes champion few years from now in future.
Interestingly enough E4 route would be logical way for Misty to go down as well, considering how her dream was to become water master(best water trainer in world) never achieving it. And her game counterpart in Gold and Silver did said how she plans to travel in future to grow stronger making sense from game perspective too
Her game counterpart was a dragon master and gym leader, and 2 years later became champion (which isn't a huge leap from Gym8).
Since her Anime counterpart is still working towards the level of her B&W game counterpart, in seems fairly obvious the "champion status" isn't happening during her anime run.
Actually her game counterpart started to be referred as dragon master once she got promoted to champion.