Well, sometimes in fanfiction, authors like to explore dark and twisted ideas. Maybe they want to create a contrast to the kind Molly Weasley in the original series. It could be a way to add drama and conflict to the story, even if it's a bit out of character for the Molly we know.
Some Hermione fans might be outraged. They love Hermione and seeing her hurt in such a way, especially by a character like Molly who is supposed to be good, could make them very angry at the writer.
It could create a rift in the friendship between Hermione and the Weasley family. If Hermione is hurt, she might distance herself from them. This would be a big change as the Weasley family has been like a second family to Hermione. It would also affect Ron, who is in love with Hermione. He would be caught in the middle between his mother and Hermione, which could add a lot of drama to the story.
One possible scenario could be a misunderstanding. Maybe Molly misinterprets Hermione's actions regarding Ron. For example, if Hermione is being strict with Ron about his studies or his behavior in the fanfiction, Molly, being Ron's mother, might take it the wrong way and say something harsh to Hermione, thus hurting her. Another situation could be related to Hermione's Muggle - born status. If in the fanfiction, there are some rising tensions about pure - blood and Muggle - born wizards, Molly, who is from an old wizarding family, might accidentally let her old - fashioned views slip and make a comment that offends Hermione.
Harry would also be very protective of Hermione. He would likely step in between Molly and Hermione, using his status as the Boy Who Lived if necessary to defuse the situation. He might try to reason with Molly, reminding her of all the good things Hermione has done for them and for the wizarding world.
Well, in some fanfictions, it might be because of a misunderstanding. Maybe Hermione's actions are misinterpreted by Molly. For example, if Hermione is too focused on her studies or magic research and seems to neglect the family values that Molly holds dear, Molly could start to dislike her. Another reason could be that Molly is overprotective of her son Ron, and she might think Hermione is too pushy or controlling in their relationship.
In some fanfictions, Hermione might please Molly Weasley by showing great respect for the Weasley family traditions. For example, she could participate wholeheartedly in the preparation of family feasts, using her intelligence to follow Molly's recipes precisely. She might also use her magic skills to help around the Burrow, mending things or cleaning in a way that Molly appreciates.
I'm not sure if there is a specific fanfiction with that exact title. However, fanfiction websites like FanFiction.net and Archive of Our Own have a vast collection of Harry Potter fanfictions. You could try searching for key words related to Molly Weasley, Hermione, and any relevant themes there.
One possible reason could be jealousy. Maybe Molly is jealous of Hermione's intelligence and the special bond she has with Harry and Ron. Another reason might be that she feels Hermione is a bad influence on her sons in some way. For example, she might think Hermione's Muggle - born status could bring trouble to the family in the wizarding world which is full of pure - blood supremacist ideas.
Hermione might run away crying. This would be a common reaction as she is a sensitive person. She could then go to Harry for support, and they might come up with a plan to resolve the issue with Molly.