I find it difficult to believe she could be the champion being an "aspiring" journalist and what not. Not that the champion of a region can't strive to pursue another path, it's just that I can't imagine a person who has traveled all around the region, met so many different and interesting people and became the top Pokemon Trainer of a region finding it at all that difficult to become a journalist. Sure it's possible but I feel it would be easily attainable.
I think she'll be similar to the reporter at the end of Pokemon (Gold/Silver?) that tries to interview you after defeating the Elite Four. But instead will play a bigger role and follow you on your journey writing various pieces on you and the evil team. Ultimately making you quite popular within the region by the end of the game.