One possible plot could be Izuku discovers his energy manipulation quirk has a unique side - it can interact with different dimensions' energy. He accidentally opens a small rift during a training session. This leads to a series of events where he has to learn to control his quirk better to close the rift before it causes chaos. He teams up with his classmates, using their quirks in combination with his to stabilize the rift.
Izuku could develop in terms of his relationships. His energy manipulation quirk makes him stand out more. Some people may be jealous, while others are in awe. He has to learn to deal with these different reactions. He may form closer bonds with those who support him and his quirk development. At the same time, he tries to understand the ones who are jealous and convert them into friends or at least neutral parties. This process of handling relationships matures his character.
He could start by training to absorb more types of energy. For example, if he can currently only absorb physical energy like kinetic or thermal, he could learn to absorb electromagnetic energy too. This would open up new possibilities for his quirk usage. Another way is to increase the efficiency of his absorption. Maybe he can work on reducing the time it takes to absorb energy or increase the amount he can hold at once.
The Gamer Quirk also changes Izuku's relationship with others. He can now offer unique insights based on his quirk. For instance, he might be able to analyze a villain's attack pattern like it was a boss fight in a game. His friends and allies can then use this information to their advantage. This makes him a valuable member of any team. At the same time, it also means that he might be seen as a bit of an oddball because his thinking is so different from the norm. But overall, it helps him form deeper connections with those who understand and appreciate his quirk.
A great plot idea could be Izuku finding out that his energy absorption quirk is related to an ancient power. He then has to go on a journey to discover the origin of his quirk, meeting different characters along the way who either help or hinder him. Also, he could face a villain who has a quirk that nullifies his energy absorption, forcing him to rely on his other skills and the support of his friends. And perhaps he discovers that his quirk can be used not only to absorb but also to transfer energy, which could lead to some interesting team - up scenarios.
In 'The Healer of UA', Izuku's healing quirk is more complex. It requires him to concentrate and visualize the injury being healed. He can also transfer some of his own stamina to the injured to speed up the process. This makes his quirk not only about physical healing but also about his own sacrifice and determination.
In fanfiction, Izuku often has unique ways to cultivate his quirk. One common scenario is that he focuses on intense physical training. Since his body was initially not as strong as it could be to handle his powerful quirk, he might do a lot of strength - building exercises like weightlifting and running. This not only helps him control his quirk better but also increases his overall combat capabilities.
Bakugo is often paired with Izuku. Their relationship is complex in the original series, and in fanfiction with Izuku's time quirk, it could add more depth. Bakugo might be jealous of Izuku's new power at first but then come to respect it as they face challenges together.
There are also fanfictions where Izuku's quirk has a hidden aspect. Maybe his connection to One For All unlocks memories or abilities from the previous users in a more profound way. For instance, he might be able to access the combat knowledge of the past users directly, almost like having an in - built combat instructor guiding his every move.
His relationships with others might change. His friends could view him in a new light, either with admiration or envy. Enemies might start to target him more, seeing him as a greater threat now that his quirk is unlocked.