Maybe Frilish is causing trouble in a local area, and Ash decides to catch it to restore peace. Along the way, he might learn some new strategies or form new friendships with other characters in the fanfiction world.
One possible plot could be that Ash discovers Frilish in a mysterious new region and has to overcome various obstacles like other Pokémon trainers or difficult terrains to catch it.
Well, I don't have a particular 'ash catches frilish fanfiction' at hand. However, when looking for such fanfiction, you can use relevant tags on fanfic platforms. Maybe start by searching for Pokémon - related fanfiction platforms as Ash is from Pokémon, and then narrow it down with 'frilish' in the search options. This way, you might be able to find some interesting stories.
One possible plot could be that Ash stumbles upon the shiny pokemon by pure chance while exploring a new, uncharted area. Maybe he's looking for a specific type of pokemon for a local competition and instead, he discovers this rare shiny pokemon. Another plot could involve the shiny pokemon being in danger from a group of poachers, and Ash has to rescue it. Then, after rescuing it, he forms a special bond with the shiny pokemon which is different from his bonds with his other pokemon.
One possible plot is that Latias is injured and Ash finds it. He nurses it back to health, and during this process, they form a bond. Latias then decides to join Ash's team. Another plot could be that there is a tournament where the prize is a special item that can attract Latias. Ash enters the tournament, wins, and uses the item to catch Latias.
A possible plotline could be that Fennekin is a rare and special Fennekin that only appears in a certain region. Ash hears about it and goes on a quest to find it. After a long search, he finally encounters Fennekin. Through a series of events, like helping Fennekin out of a dangerous situation, he earns Fennekin's trust and catches it.
One interesting plot could be that Ash catches a shiny Pikachu which has some unique powers, like being able to communicate telepathically with other Pokemon. This would change the way Ash interacts with his team and the challenges he faces in battles.
One possible plotline could be that Ash stumbles upon Latias while exploring a new region. Latias is initially shy but Ash's kind nature draws her in. They start to form a bond as Ash helps Latias when she gets injured by some wild Pokémon. Another could be that Latias is being chased by a group of poachers and Ash steps in to protect her. This leads to an adventure where they have to outwit the poachers and in the process, Latias decides to stay with Ash for a while.
Well, one possible interesting plot could be Ash using his unique bond with his Pokémon to outwit Mewtwo. Maybe he convinces Mewtwo that not all humans are bad through the kindness shown by his Pokémon team.
A plot could be that a lemon - loving Pokémon starts causing trouble in the area where Ash and Squirtle are. Ash and Squirtle team up to stop it, and along the way, they discover that the lemon - loving Pokémon has a sad backstory related to being over - hunted for its love of lemons. They then try to find a way to protect it and also satisfy its lemon cravings in a more sustainable way.
One possible plot could be that Latios is in danger from a powerful and evil Pokémon trainer. Ash discovers this and uses his Pokémon team to battle the trainer and rescue Latios. For example, Ash might use Pikachu's electric attacks in a strategic way to overcome the enemy's defenses.
Maybe in the fanfiction, there's a special event where all Pokémon transform into their child forms for a short time. Ash meets child - Latias during this time. They enter a Pokémon competition specifically for these transformed Pokémon. Ash and Latias have to work together to overcome the other competitors, who also have some strong Pokémon combinations. They learn about teamwork and the importance of believing in each other during this adventure.