Another reason could be that the fanfiction doesn't respect the growth and development of their relationship. Annabeth and Percy have a deep, evolving bond. If the fanfiction simplifies it or takes it in a direction that doesn't align with how their relationship should progress, it would make her dislike it.
One possible reason could be that the fanfiction misrepresents their characters. Maybe it portrays Percy in a way that Annabeth doesn't like or goes against the essence of their relationship as she sees it.
It might be that the high school setting in the fanfiction is too clichéd for her. Annabeth is a complex character and perhaps she feels that the typical high school drama scenarios in the fanfiction don't do justice to their story. For example, if it reduces their epic adventures to simple high school rivalries, she would likely hate it.
Chapter 287, "Cloud Dragon Army's First Battle, Zhou Yuan's Bloody Struggle, Decisive Victory and Unexpected Windfall (Part 3)", is the clearest early answer because the buildup finally cashes out in a real clash. Early on, The problem is, they still can't make any counterattacks.. By the end, The banner flapped wildly in the battlefield wind, and the Cloud Jiao....
Chapter 296, "Keen Instincts, Rallying the Troops, Bai Qiucheng's Cunning Scheme", is the clearest early answer because it turns Xia Hong's situation into a concrete plot event. It opens with The forty-eighth year of Longyou, June 22 At the first light of dawn,... and closes on Not only is the cost low, but the manpower required is minimal, apart....
Chapter 224, "Cold Resistance Level Classification, Gains and Persuasion", is the clearest early answer because Long Mountain finally turns buildup into a real advancement. The chapter turns that into something concrete by moving from The total area of Longyou is about more than thirteen thousand square... to Just breaking through the Cold Resistance Level counts as the early....
Chapter 307, "Silver Mine News, Uprisings Everywhere (Part 3)", is the clearest early answer because it turns Great Xia's situation into a concrete plot event. The chapter turns that into something concrete by moving from Wu Tianxing hastily cupped his hands and replied, "This time it's in... to Near the entrance to the western dungeon, at least fifteen thousand....
Chapter 218, "Departure, Sending a Letter, Killing (Part 2)", is the clearest early answer because it pushes Great Xia into a new phase or setting. The setup is Xia Hong adjusted the mask on his face, then pretended to push the..., but the pressure keeps building through Second Year of Great Xia, April 5th Ten miles north of Jing Valley,....
Chapter 278, "Thousand-eyed Demon Sheep, Terrifying Power, and Spiritual Medicine", is the clearest early answer because the rescue effort creates visible on-page results. The chapter gives readers a real answer by opening on Roar!" After the muscles all over the Demon Sheep's body stopped... and ending on The two, who had narrowly escaped death, saw that it was Xia Hong who....
Chapter 309, "Gamblers at the End of the Road, Li Family's Swan Song", is the clearest early answer because it turns Meng Ying's situation into a concrete plot event. The chapter gives readers a real answer by opening on As daylight arrived, the biting cold light spread over the earth, and... and ending on Beside him, Li Xuanqiu was shaking with rage, directly reprimanding:....
Chapter 251, "Understanding—Win Hearts First, Then Take the Next Step (Part 2)", is the clearest early answer because it turns Xia Hong's situation into a concrete plot event. The chapter turns that into something concrete by moving from As for Xia Chuan, he didn't even open his mouth, just furrowed his... to Even if implemented, the number of mining slaves must be strictly....
Chapter 223, "Outbreak of Battle, Breaking the Siege, Honored Guest", is the clearest early answer because the buildup finally cashes out in a real clash. A useful checkpoint is the way the scene starts with As his name suggested, Hou Hu's image was not much different from... and follows through with The humans from the Ice Abyss Camp had hunting Cold Beasts as a....
Chapter 236, "White Dew Gu, Despairing Yuwen Dao, Yang Lu", is the clearest early answer because it turns Xia Chuan's situation into a concrete plot event. It opens with Now that things have come to this, the destruction of Yanglu Camp is... and closes on Great Xia Minister, Xia Chuan, Leader Peng, I'm quite interested in.... The key payoff is that the chapter closes with "Alright, Leader Peng is straightforward.