Well, one possibility could be that Adrienne somehow gets turned into a baby or regresses to a diaper - wearing state in the Pokemon world. Maybe there's a strange Pokemon power or a magical event that causes this. And then the story could be about how the Pokemon around her react, perhaps some of them try to take care of her like Pikachu bringing her berries or a water - type Pokemon getting water for her. It could also involve her trying to communicate with other trainers in this new state, which would be really difficult and lead to some comical or heartwarming situations.
Pikachu could be one of the main characters. Since Pikachu is so friendly and curious in the Pokemon world, it might be the first to approach Adrienne when she's in this new state. It could try to play with her or protect her from other Pokemon that might be a bit too rough. Another character could be Ash. Ash has a lot of experience with different Pokemon and strange situations. He might come across Adrienne and decide to help her. He could use his knowledge of Pokemon to find a way to get her back to normal or at least keep her safe while she's in this diaper - wearing state.
One possible theme could be about caregiving. It might explore how someone takes care of Adrienne while she is in diapers, showing a nurturing side. Another theme could be related to her vulnerability in that state, perhaps highlighting her need for support.
In the fanfiction, it could be that Touko has been turned into a baby or a toddler - like form by a powerful and mischievous Pokemon's spell. As a result, she is wearing diapers. Her Pokemon team has to take care of her as if she were a young child, and she has to learn how to communicate with them in a new way while she tries to find a way to break the spell.
Perhaps it's a fantasy - themed fanfiction. Adrienne could be in a magical world where she's been transformed into a younger state, and being placed in a diaper is part of the new reality she has to face. This could lead to adventures as she tries to find a way to reverse the transformation while dealing with the embarrassment and challenges of her new situation.
It could be about girls who for some reason, like a magical event or a strange experiment, find themselves back in diapers. Maybe they have to relearn basic skills while in this situation.
I'm sorry, but I don't have specific Adrienne wearing diapers fanfiction to recommend. You could try searching on fanfiction platforms like Archive of Our Own or FanFiction.net, where you might find relevant stories by using relevant tags.
Maybe a group of young trainers are taking care of baby pokemon in diapers at a daycare center. They face challenges like diaper changes, feeding, and also protecting the pokemon from wild pokemon attacks. It could be a cute and comical story.
I'm not aware of any such Pokemon fanfiction. It's a rather unusual and unseemly topic for a fanfiction, and most Pokemon fanfiction tends to focus on more positive aspects like battles, friendships, and adventures in the Pokemon world.
Well, a plot could be where Ash travels to a strange region where there is a custom that all trainers start their journey as babies in diapers for some unique reason related to the local Pokemon lore. Ash has to adapt to this new way of starting his adventure while also facing the typical challenges of training Pokemon. Or perhaps there's a time - travel aspect where Ash goes back to his own baby days in diapers and has to use his future knowledge to help his younger self and the Pokemon in that time period.
Her best friend could be a main character. They might be the one who discovers Adrienne's situation and either helps her or is the cause of it, depending on the plot. For example, if it's a medical situation, the friend could be the one who calls for help or stays by her side.