In a Gaston kidnaps Belle fanfiction, a great plot twist might be that Gaston's sidekick, Lefou, has a secret alliance with Belle. He might have grown tired of Gaston's overbearing and cruel behavior. So, when Gaston kidnaps Belle, Lefou actually helps her escape. He could create distractions, like starting a small fire in Gaston's hideout or making false alarms about approaching villagers. Another interesting twist could be that Belle discovers she has some latent magical powers of her own during the kidnapping. These powers could be related to her love for books and knowledge. For example, she could make words from the books she's read come to life to fend off Gaston.
One possible plot twist could be that Belle's father, Maurice, teams up with the enchanted objects in the Beast's castle to rescue her. Since Maurice has been to the castle before, he might know some secret passages or ways to get in undetected. Another twist could be that Gaston has an unexpected change of heart during the kidnapping. Maybe he realizes the error of his ways when he sees Belle's true distress and decides to let her go. However, this would be a huge character shift for him given his egotistical and self - centered nature in the original story.
Well, in this fanfiction scenario, a plot twist could be that Belle uses her wits to turn the tables on Gaston. She could start by pretending to be compliant and then when the time is right, she could lead Gaston into a trap. It could be a trap set by the forest animals who have become her friends. They could use their natural abilities like the birds flying at Gaston's face to disorient him, and the squirrels and rabbits could lead him into a maze - like part of the forest where he gets lost. Another idea is that the Beast, in his love for Belle, overcomes his fear of the village and goes to rescue her. He could bring along some of his magical powers from the castle to defeat Gaston.