Alastor and Charlie trained Izuku for years so then he can control his power,he had got breaks so then he could hang out with his friends, Izuku did tell them about his training with the king and queen of hell and they didn't believe him at first but after showing them they started to believe him.
After 12 years he looked like Alastor and had the personality of Alastor and Charlie mixed, the day of the exam came and he had been trained to the point where he could defeat All might with one flick of a finger, Izuku looked up at UA and said. "Thank you Alastor and Charlie for training me. I won't let you down." And walked inside.
He went to written exam room and analyzed the examinees and he saw Katsuki Bakugou, his best friend and his quirk was Angel dust and flying hellcat (I am giving him two different quirks instead of his original quirk so please don't judge me) and he looked like husker, Alastor's best friend, and as he saw him walking up the aisle, he waves to him Izuku sat down he said. "So wassup king of hell." Izuku said. "Everything is going alright katsuki." (Also instead of calling him Kacchan he is calling him by his first name.)
Present Mic started explaining the rules of the written exam and physical exam, as he started explaining the fourth robot Iida stood up raising his hand saying. "Sir, You forgot a robot and that is very hero-like!" waving his hand in a very robot-like way, Izuku stood up and released bloodlust, and said. "If you keep interrupting I would suggest you go join hell instead of UA, and plus he was about to explain the fourth robot" And as he sat down He sealed up his blood lust so then they could do the test with concentration instead of being filled with fear, Iida then sat down and said. "I am sorry for my behaviour." Present Mic then said. " It is ok little listener and thank you other little listener." Izuku then said. "Your welcome Mic." and sat down, as Mic was passing the papers, he explained that there is no cheating and if anybody did cheat they would get kicked out, when Izuku looked at it he knew instantly that this answers were super easy since he had a better IQ then Nezu and as looked closer there were grammar errors in there, 15 minutes later he stood up and walked to the front to give Mic his paper, as he gave it to him he whispered. 'You need to make these answers harder and there are grammar errors in there as well.' Mic looked surprised as he left.