In some fanfics, it could be through a magical artifact that Seto uses. For example, he might find an ancient amulet that gives him the power to control Joey's mind.
Another great fanfic could be 'Breaking the Chains'. In this, Joey is under Seto's mind control at first, but then with the help of his friends, he starts to resist and fight back. It shows the power of friendship and determination over mind control.
The main characters are Joey and Seto, of course. Joey is often depicted as a more impulsive and passionate character, while Seto is more calculating and reserved. In the context of mind control fanfiction, their personalities play a big role in how the story unfolds. Joey might be more vulnerable to the mind control in some stories because of his more emotional nature, while Seto would be the one trying to figure out what's going on and find a solution.
One possible plotline could be that the mind control is used as a way to make Joey and Seto understand each other better. For example, through the mind control, Seto might see Joey's insecurities and the real reasons behind his actions. Another could be that an external force uses mind control on Joey to make him do things against Seto, creating a lot of conflict and drama as Seto tries to figure out what's wrong with Joey and how to break the control.
One common theme is rivalry - their long - standing competitive nature in the Duel Monsters realm. This often serves as a starting point for the relationship to develop.
A common theme could be the exploration of their relationship dynamic. Given their different personalities in the original Yu - Gi - Oh! series (assuming they are from there), fanfics might focus on how they overcome their differences. For example, Seto's cold and calculating nature vs Joey's more hot - headed and impulsive one.
Another great 'joey x seto fanfic' could be 'A New Alliance'. This fanfic starts with Joey challenging Seto to a series of duels with a wager. As the duels progress, they begin to understand each other on a deeper level, and the story unfolds with some really interesting character development.
In a great Seto Kaiba x Joey Wheeler fanfic, the relationship development is key. It should be believable and not rushed. The writer needs to show how they gradually come to understand and care for each other. Also, the writing style is important. A vivid and engaging style can bring the story to life, making the reader feel as if they are right there with Kaiba and Wheeler. Good fanfics might also incorporate elements from the Yu - Gi - Oh! universe in an interesting way, like using the Duel Monsters cards as a metaphor for their relationship.
I'm not sure about specific Seto x Joey Lemon fanfic, but you can start by looking on popular fanfiction websites like Archive of Our Own (AO3). There are usually a wide variety of fanfictions for different pairings there. Just search for 'Seto x Joey Lemon' in the search bar and browse through the results.