The new quirk of Deku is quite exciting and adds a new dimension to his powers. But I don't want to spoil it for you. You should read the manga to find out!
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.
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.
A well - liked fanfiction is 'Midoriya's Dual Quirks'. As the title suggests, he gets not one but two quirks. This makes for an interesting read as he has to balance using both and figure out how they interact. There's also 'The Forbidden Quirk' where Midoriya gets a quirk that is considered dangerous or taboo in the My Hero Academia universe. It creates a lot of conflict as he tries to keep it a secret while also using it for good. And 'Quirk of the Ancients' where his new quirk has roots in an ancient, long - forgotten power source, leading to a journey of discovery about the history of quirks.
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.