There could be unfinished business between them. They might have a shared goal that they haven't achieved yet. Greninja's return to Ash in the fanfiction could be to finally complete that goal, whether it's winning a particular Pokemon tournament or saving a certain place from destruction.
In this fanfiction, Ash could develop better strategic thinking. Froakie's abilities would force Ash to come up with new battle plans. He'd study Froakie's moves and how they can be combined in different ways, thus enhancing his strategic skills. He may also become more empathetic towards Froakie as he discovers more about its nature and feelings, leading to a more well - rounded character.
Perhaps it's a story where Ash and Froakie form an even deeper bond than in the original series. They might go on a quest to find a rare Pokemon that only Froakie can sense, and along the way, Ash learns more about Froakie's past and its potential. Froakie could also teach Ash some new strategies in battles that help him become a better trainer overall.
I'm not sure of a specific 'ash starts with froakie fanfic' off the top of my head. But you could try searching on fanfiction websites like FanFiction.net or Archive of Our Own. They have a vast collection of Pokémon - related fanfics, and you might be able to find one that meets your criteria.
One possible plotline could be Ash and Froakie's journey to become stronger together. They might face various challenges in Pokémon battles and overcome them with their bond. Another could be Froakie having some special ability that Ash helps it to discover and master.
One popular Ash and Ash - Greninja fanfiction could be those that focus on their adventures in a new, unexplored region. In these stories, they might face unique and powerful Pokémon, strengthening their bond along the way.
Well, in Alola, the battle environment is different. Ash Greninja has to adapt to the new battle rules like Z - Moves. It may start by observing local battles and learning from them. It could also adapt to the more friendly and less intense battle atmosphere compared to other regions. This means it might have to change its battle strategy a bit, not always going all - out from the start. And it might interact with different types of Pokemon that are native to Alola, which could lead to new friendships or rivalries, further shaping its adaptation to the Alola environment.
The fanfic could focus on Ash and Froakie's bond in Kanto. Maybe they get separated in a dense forest in Kanto and have to find their way back to each other. Along the way, Froakie discovers its hidden strengths and Ash learns more about the unique Pokémon in Kanto that he hadn't known before.
I'm not a big fan of yaoi fanfiction in general, but in the case of Greninja and Ash, it often involves a creative exploration of their relationship in a non - canonical way. Some of these fanfictions might focus on their strong bond and translate it into a more romantic or emotional connection that goes beyond friendship as seen in the original Pokemon series.
Well, it could vary a great deal. In some 'ash greninja returns fanfiction', it might focus on Ash and Greninja reuniting after a long separation. Maybe Greninja has been in a far - off place training or on a mission, and now it comes back to Ash to help him in a big battle. They then team up again, with Greninja using its unique Water - Shuriken and other moves to take on powerful opponents.