Perhaps they go on an adventure together in Alola. They could discover a new and rare Pokémon species. Ash's courage and Lillie's kindness would make them a great team in exploring the Alola region.
In fanfiction, Ash might help Lillie become more confident in her Pokémon training. Since Ash is an experienced trainer, he could share his knowledge and skills with her.
In fanfiction, when Ash meets Serena in Alola, they might go on a new adventure together. They could explore the unique Pokémon in Alola and share their experiences. Maybe Serena would be excited to see all the new Pokémon forms and Ash would show her around his new stomping grounds.
Another plot point could be that they team up to face a powerful enemy in Alola. It could be a new Team Rocket - like organization or a wild and dangerous Pokémon. Their combined skills and the Pokémon they have would be crucial in this fight.
In this fanfiction, Ash might make new friends in the Alola region. He could encounter unique Pokémon there that he has never seen before, like the Alola forms of some Pokémon.
Maybe they'll go on an adventure together in Alola. Red could be amazed by the unique Pokémon species in Alola, and Ash could learn from Red's experiences with Pokémon from other regions. They might also team up to face some tough opponents and show off their combined skills in Pokémon battles.
Well, it could be about Ash exploring the unique Pokémon in Alola. Maybe he discovers new forms of old Pokémon and has exciting battles with local trainers.
In fanfiction, Ash and Greninja might have all kinds of adventures in Alola. They could encounter new Pokémon species that are unique to Alola. Greninja could show off its skills in the new environment, impressing the local trainers. Maybe they'll participate in the Alola Pokémon League together and face strong opponents.
In fanfiction, when Ash takes Charizard to Alola, they might have all kinds of adventures. Charizard could help Ash in battles against the unique Alola Pokémon. It could also be a chance for Charizard to interact with new Pokémon species and form new friendships or rivalries. Maybe it would even learn some new moves from the local Pokémon trainers or from the environment of Alola.
In fanfiction, when Serena visits Ash in Alola, they might go on new adventures together. Maybe they explore the unique Pokémon in Alola, like going to find a rare Alolan Vulpix. They could also participate in local Pokémon battles and festivals, strengthening their bond all the while.
One possibility is that Ash's adventures would change. He might not be able to go on long journeys as easily with a baby at home. So he could focus more on local adventures or teaching his child about Pokémon.
Ash could discover a new form of an existing Alola Pokemon. This new form could be the result of some kind of special evolution due to the unique energy in the Alola region. His friends would be amazed, and they would all help him research and understand this new discovery.