Snotlout's protectiveness in How to Train Your Dragon fanfiction can range from being fiercely protective to only moderately so. It often depends on factors like the relationships he has and the challenges he faces in the particular fanfic.
Start by getting a clear idea of Snotlout's personality and motivations. Then, come up with an exciting plot that shows his growth or adventure. Make the story have some unexpected twists to keep readers hooked.
To pen this fanfiction, get into the minds of Snotlout and Ruffnut. Understand their motivations and dreams. Then, create a story that either expands on the existing canon or takes a creative detour while staying true to their characters.
The fanfiction might present Hiccup and Snotlout fighting because of a rivalry that has been brewing for a while. It could also be that an external threat forces them into a confrontation where they have different strategies.
Well, the bodyswap could be triggered by a rare magical artifact in the story. Or it might be the result of a curse placed by an evil sorcerer. Different fanfictions have their own creative explanations for it.
The body swap might occur during a dream sequence where their subconscious minds switch places. Or it could be the result of a time-traveling glitch that messes with their bodies. Maybe a cursed treasure they both try to claim causes the swap.
One popular theme is the further adventures of Hiccup and Toothless. Writers often explore new lands and challenges that they might face. For example, they might encounter a new type of dragon with unique abilities.