Well obviously FiM would need to be canon to EG or else EG wouldn't exist without pre-established canon I honestly think Starlight is far better anyway. Everyone gripes on about the fact that oh she was forgiven too quickly and how shimmer had to earn forgiveness. In all honesty Starlight makes more sense since the show is all about friendship and forgiveness. SHe also made a much better villain and her methods made much more sense. Shimmer just wanted to be evil and to rule equestria so she stole the crown and turned into a demon of sorts. Starlight was doing what she thought was good, she felt cutie marks tore people apart since that's what happened to her, her parents weren't around either so after that she was all alone and it ate at her so she made a village where no one has cutie marks and where no one is special. She didn't know any better. But despite all that people still whine because she was forgiven in a show about forgiveness.