Another aspect could be Loki's relationship with the other characters. Without Thor, he would need to build new alliances. He could form an unexpected bond with Hulk, perhaps using Hulk's brute strength and his own cunning to create a unique duo. They could then set out on a mission to retrieve the Infinity Stones from Thanos, with Loki devising elaborate plans and Hulk providing the muscle.
Loki could gain the ability to harness Thor's lightning. Maybe in the moment of Thor's death, some of his power transfers to Loki. This would be a huge boost to Loki's combat abilities and could make him a more formidable opponent against the likes of Thanos.
One way Loki could survive Infinity War in fanfiction is through his shape - shifting abilities. He could have faked his own death by creating an illusion of himself being killed by Thanos while he actually slipped away. Another possibility is that Heimdall, using the last of his power, sent Loki to a hidden realm before Thanos could deal the fatal blow.
One way Loki could survive in a fanfiction of Avengers Infinity War is if he used his illusions more cleverly. He could have created a very convincing double of himself to be killed by Thanos while he escaped. Maybe he used his magic to teleport at the last moment to a hidden location in Asgard or even a different realm.
Loki's survival might also lead to a shift in power dynamics. In the Asgardian remnants, he could emerge as a leader figure, using his wits and magic to protect and guide them. This would change the way Asgardians are perceived in the MCU. Instead of being a broken and defeated people, they could become a force to be reckoned with under Loki's leadership.
One way to 'fix' the situation in a fanfiction could be to have Loki's faked death in Thor: The Dark World be more thoroughly investigated by Thor. If Thor had been more suspicious and dug deeper, he might have uncovered Loki's real plan earlier. This could have led to them working together more effectively against Thanos in Infinity War, preventing some of the tragedies that occurred.
If Loki survived in Infinity War fanfiction, it could have led to a very different outcome. He might have used his trickery to deceive Thanos in some way. Maybe he could have pretended to be on Thanos' side while actually working against him. This would have added an extra layer of intrigue to the story as the other characters would have been unsure of his true motives.
A possible plot twist could be that Loki was actually working with Thanos all along, but faked his death to deceive the Avengers. This would change the whole dynamic of the story and lead to a new set of conflicts. Another twist could be that Loki's survival was part of a grand plan by Odin (who might not be truly dead) to stop Thanos from getting all the Infinity Stones.
Their relationship could have become stronger. After Loki's 'death' in the movie, Thor was devastated. If Loki survived, Thor would likely be more protective of him. They might start to trust each other more fully, putting aside their past differences.
In fanfiction, Loki and Thor could have formed an alliance with other unexpected characters during Infinity War. Maybe they would team up with the Guardians of the Galaxy in a different way. Loki could have used his knowledge of the cosmos and his ability to blend in to gather more information about Thanos' plans. Thor could have shared his Asgardian battle strategies with Star - Lord and the others. This would have led to a completely different dynamic in the fight against Thanos, perhaps even resulting in a victory that didn't happen in the movie.
In some fanfiction, it shows a more reconciled relationship between Loki and Thor in Infinity War. Instead of the conflicted and somewhat hostile relationship in the movie, they are shown to be more understanding of each other. Loki might be more open about his fears and Thor more accepting of his brother's past actions.