One common theme is brotherhood. Since they are like brothers in the original story, fanfics often explore and strengthen this bond. Another theme is adventure. They are all adventurous characters, so fanfics usually involve them going on exciting quests.
One possible plot could be a grand adventure where they team up to take on a powerful enemy that threatens the safety of their hometown. They could use their combined skills and the strong bond they share to overcome challenges.
One great 'ace luffy sabo fanfic' is 'The Brothers' Bond'. It beautifully portrays their relationship and the adventures they might have had together. Another is 'Sabo's Return', which focuses on Sabo coming back into Luffy and Ace's lives in a very emotional way.
One popular Sabo x Luffy fanfiction is 'The Brothers' Bond'. It beautifully explores their relationship with lots of emotional moments. Another good one could be 'Sabo and Luffy: New Adventures' which takes them on a whole new set of exciting quests. There's also 'Sabo, Luffy: Reunion' that focuses on their reunion and how it impacts their future.
In fanfiction, when Sabo and Luffy meet again, they might have an emotional reunion. They could share stories of their adventures since they last saw each other. Sabo might show off his new skills or powers, and Luffy would be excited to see his brother again. They could also plan new adventures together, vowing to face any challenges as a team.
Their relationship would likely deepen. They would have a stronger bond as brothers. They might understand each other's dreams and goals even better. Sabo would support Luffy's pursuit of the One Piece more actively, and Luffy would be more aware of Sabo's role in the revolutionary cause.
Their reunion would likely cause a stir in the pirate world. Other pirates would see them as a very powerful group. It could also inspire many young pirates to strive for stronger bonds with their comrades, just like Luffy, Ace and Sabo.
Another interesting one is 'Sabo's Return: With Ace'. In this story, Sabo returns much earlier than in the original story. It details how he and Ace reunite and the impact it has on the Straw Hat crew and the overall One Piece world. The story is full of action and heart - warming moments between the two.
I really like the fanfictions that involve Ace, Whitebeard and Sabo. They are such interesting characters. In many of these fanfictions, the relationship between them is explored in great depth. For example, how Sabo copes with having Ace as his 'brother' again after thinking he was dead. And Whitebeard's role as a father figure to them adds another layer of complexity and warmth to the stories.