Well, one possible plot could be that Ron, as a girl, has to navigate the different social dynamics at Hogwarts. She might struggle with how the boys now treat her differently, and the girls might be either overly friendly or jealous. Maybe she would use her new form to get closer to Hermione in a different way, like understanding her on a more 'female - to - female' level. Also, she could have a whole new perspective on her own family, especially how her mother treats her now as a daughter in a different sense.
Perhaps the plot would focus on Ron's transformation as a girl leading to her discovery of new magical abilities or talents. In the wizarding world, gender might play a role in certain types of magic. As a girl, she could find that she has an affinity for spells or potions that were previously difficult for her as a boy. She could then use these newfound abilities to help her friends, like Harry and Hermione, in their adventures. This would also be a journey of self - discovery for her, as she realizes that there are aspects of herself she never knew existed.