One interesting plot point could be how they handle their different Pokémon - training styles. Ash is more impulsive and befriends Pokémon easily, while Clair is more traditional. Their marriage could be a journey of learning from each other in that aspect. Another could be dealing with family reactions. Ash has his mom and friends, and Clair has her family in the Dragon's Den. How they all react to the marriage and blend their families could be really engaging.
One interesting plot point could be the reactions of their Pokémon. For example, Pikachu might be a bit jealous at first because Ash is spending so much time with Cynthia. Another plot point could be the cultural differences between Kanto (where Ash is from) and Sinnoh (Cynthia's region). They could incorporate elements from both cultures into the wedding. Also, a plot point could be the challenges they face before the wedding, like an evil team trying to disrupt the event because they fear the power of their combined Pokémon knowledge and skills.
One plot idea could be that Clair challenges Ash to a special battle where the loser has to fulfill a strange request. For example, if Ash loses, he has to help Clair train a particularly stubborn Dragon - type Pokémon for a month. Another idea is that they team up to explore an ancient, mysterious cave filled with rare Pokémon and hidden secrets about the Pokémon world. Maybe they discover an old prophecy that involves them and their Pokémon.
Another interesting plot point could be the combination of abilities. Imagine Naruto using his shadow clone jutsu and Clair's Pokemon using moves like Double Team. They could create some really complex and cool battle strategies. Also, if there are bad guys involved, like Team Rocket from Pokemon and the Akatsuki from Naruto, they could team up to cause more chaos, and our heroes would have to figure out how to stop them. This would involve Clair using her knowledge of Pokemon types and Naruto using his ninja wisdom.
One interesting story could be about Ash and Clair teaming up to face a powerful and rare Pokemon. They might have to combine their skills and knowledge to overcome it.
I'm not sure about specific 'ash and clair married fanfiction' offhand. But you could try searching on popular fanfiction websites like FanFiction.net or Archive of Our Own. They usually have a wide variety of fanfictions, and you can use the search function to look for stories specifically about Ash and Clair getting married.
Well, in many such fanfictions, it could involve Ash being betrayed by Clair perhaps in a Pokémon battle strategy. Maybe Clair teams up with an unexpected rival against Ash, or she might break a promise regarding Pokémon training or a joint adventure.
In a fanfiction, perhaps Clair betrays Ash because she believes he's not a worthy trainer. She might think that Ash's methods are too haphazard and that he's endangering the Pokemon world. So, she teams up with an organization that wants to control the Pokemon trainers, leaving Ash feeling abandoned and betrayed. This could lead to Ash having to prove himself even more to the Pokemon community and also having to face Clair in a big showdown later on.
Maybe in this fanfiction, Ash is born with a special Pokémon ability. This could lead to a plot where he has to hide this power at first because others might misunderstand or be jealous. It could also attract the attention of some evil organizations who want to use his power for their own gain.
Well, one interesting plot point could be Ash encountering new and rare Pokémon in Sinnoh that he's never seen before. Maybe he discovers a unique form of a Pokémon that's native to Sinnoh. Another could be his interactions with the Sinnoh gym leaders, like having intense battles or forming unexpected friendships with them.
Another plot point might be the relationships the reincarnated OC forms. They could have a different dynamic with Ash's friends like Brock and Misty. The OC might introduce new ideas or ways of thinking to the group, which could lead to some really fun and unexpected adventures.