An Au where Izuku is not actually happy with his life and wishes to go back in time to change everything.
The night air atop the hill was biting, carrying the distant hum of Musutafu's city lights, but Izuku couldn't feel the cold. All he could feel was the hollow, aching emptiness where One For All used to reside a phantom limb that throbbed with every heartbeat. The power that had once defined his entire existence, the legacy of countless heroes, had been sacrificed to save a soul that society had already written off. He had saved the world, but in doing so, he had lost himself.
"Please..." Izuku choked out, his voice cracking as he pressed his palms into the dirt, claws digging into the earth. "Just once more. Let me do it differently."
His green hair was matted with sweat and grime, sticking to his forehead as he bowed his head. The tears fell freely now, hot against his cheeks, carving paths through the dried salt and dust. He wasn't just grieving the Quirk; he was grieving the eight years of silence that had followed the war. The group chats that went dead, the invitations that never came, the birthdays he spent alone in his apartment while his former classmates celebrated their hero careers on television. They had moved on to a world that no longer had room for a Quirkless Deku, leaving him behind like a relic of a war they preferred to forget.
"Why does it have to be like this?" he screamed at the indifferent stars, his chest heaving with ragged, desperate breaths. "I gave everything! I gave everything to make sure you all could have a future worth living in!"
The silence of the hill was his only answer. No thunder rolled, no divine hand reached down to grant his wish. There was only the wind whistling through the grass and the crushing weight of his own loneliness."I didn't ask for this!" Izuku shrieked, the sound tearing from his throat like something physical, raw and bleeding. "I didn't ask to be left behind!"
He threw his head back, exposing his throat to the vast, uncaring cosmos. The muscles in his neck strained, and his vision blurred behind a veil of salt and grief. His heart hammered against his ribs. The frantic, terrified beat of a man who had been hollowed out from the inside. For eight years, he had lived in the periphery of their lives, a ghost haunting the edges of their success. He had watched through screens as Katsuki, Ochaco, Shoto, Yuga, Mina, Tsuyu, Tenya, Mashirao, Denki, Eijiro, Koji, Rikido, Mezo, Kyoka, Hanta, Fumikage, Toru, Minoru, Momo, all of them flourished in the spotlight he had helped build for them, while he remained trapped in the quiet, dusty halls of U.A. as a teacher who taught students how to dream of a world he no longer truly belonged to.
"Send me back!" His voice broke into a sob, his forehead slamming against the ground. "Let me go back before I lost it! Let me fight Shigaraki differently so I don't lose One For All and the people I love!"
The desperation was a physical weight, pressing down on his shoulders until he felt he might shatter. He would trade every lesson taught, every sunrise witnessed in solitude, every memory of his quiet adulthood, just to feel that spark of electricity beneath his skin one more time not just for the power, but for the connection it represented. He wanted to feel like he mattered enough to be remembered. He wanted to be more than a footnote in their heroic legends.
"Please," he whimpered against the dirt, his body shaking with uncontrollable tremors. "Just let me try again. Don't let me be alone anymore."
Essentially a time travel fix-it idea of Izuku is not truly happy with his life and wants to go back in time to change everything so he won't lose One For All. He never gotten the power suit in this.
Feel free to take this and turn it into a story if you wish.