Perhaps an ancient artifact in the MHA world has the power of the Naruto toads sealed within it. A villain discovers it first but a young hero - in - training manages to steal it away. Once in their possession, they unlock the toad quirk. They would then need to train hard to master it, just like Naruto did. They could call on the toads for help in battles, use their strong physical attacks and even learn some of the toad - related ninjutsu, adapting it to fit the rules and physics of the MHA world.
They would be very powerful. Just like Naruto can summon giant toads, this character could summon toads in the MHA world. They could use the toads as mounts or have them fight alongside. For example, they could have a toad use its tongue to grab villains and hold them in place.
One cool quirk idea could be 'Shadow Mimicry'. The user can blend into any shadow and move freely within the shadow realm, also being able to mimic the actions of those whose shadows they are in. It gives a lot of stealth and surprise attack possibilities in a fanfiction.
A fanfiction could focus on a new character with an explosion quirk who joins Naruto's team. This character might have a mysterious past related to a secret organization that was experimenting with quirks in the Naruto universe. Their explosion quirk would add a new dynamic to the team's combat strategies, and there could be a lot of fun interactions as they adjust to working together.
One idea could be an OC who discovers their psychokinesis quirk gradually. They start with small things like moving a pencil, then as they train, they can lift heavier objects. This can lead to an interesting story arc of self - discovery.
Tsuna's quirk, if we assume his Dying Will Flames are his quirk in the MHA universe, would likely be classified as an emitter type quirk. He could use his X - Burner attack as a long - range offensive move against villains. His hyper intuition could also be a part of his quirk, allowing him to predict his opponents' moves in battle. This would make him a valuable asset in hero teams, especially in complex battles where strategy is key.
He could have a quirk like 'Enhanced Intellect', which would further boost his already incredible detective skills. This would make him able to analyze situations even faster and come up with strategies on the fly.
Another possibility is a crossover with the world of Naruto. The characters from MHA could participate in the Chunin Exams. Bakugo might be really into showing off his skills in this new and different kind of competition.
One interesting idea is the crossovers between different characters from the MHA universe and other universes. For example, seeing Deku interact with characters from other popular anime like Naruto or One Piece can create really unique and exciting storylines.