One idea could be creating an OC who is a long - lost relative of one of the A - Team members. For example, a niece or nephew who has unique skills and joins the team on a special mission. This can add a new dynamic to the group and explore family relationships within the context of their adventures.
You could also have an OC who is a tech - savvy expert that the A - Team meets during one of their missions. This OC can provide new gadgets and hacking skills that help the team in unexpected ways, and their presence can create humorous situations as they interact with the more old - school members of the A - Team.
One idea could be creating an OC (Original Character) who is a new recruit to one of the teams and has to prove themselves. Another is an OC that has a special ability that changes the dynamic of the battles. For example, an OC with the power to manipulate time for a short period during a fight.
You could write an 'team natsu oc fanfiction' where the OC is from a different dimension and has different cultural norms. This OC could introduce new concepts and ways of thinking to Team Natsu. Maybe the OC's dimension has a different way of using magic, like combining it with technology, and Team Natsu has to adapt to this new form of magic while also teaching the OC about their own magic system.
One idea could be creating an OC who was originally a regular Trainer but got corrupted by Team Rocket's ideals. For example, they might have lost a big Pokemon battle and felt so defeated that they were easily swayed by Team Rocket's promises of power. Another idea is an OC who is a double agent within Team Rocket, secretly working for the good guys to bring down the organization from the inside. They could have a unique Pokemon partner that helps them in their undercover work.
One idea could be an OC who has a unique jutsu that helps Team Minato in a difficult mission. For example, an OC with the ability to control time briefly. This could create exciting scenarios where they can turn the tide of battle against a powerful enemy.
One idea could be that the OC team is on a mission to retrieve a rare and powerful ninja artifact that has been lost for centuries. This could lead to battles with other ninja clans who also want the artifact.
One idea could be that the OC team is from a parallel dimension where the rules of being a Power Ranger are different. For example, they gain their powers not from morphers but from ancient artifacts they discover in their world. Another idea is that the OC team has to team up with the original Power Rangers to fight a common enemy that threatens both their universes. This could lead to some interesting cultural clashes and exchanges of power - using techniques.
One idea could be that the OC team is on a mission to retrieve a powerful relic lost in a dangerous, abandoned Grimm-infested city. Each member of the team has a unique skill that they have to use to overcome different obstacles, like one being able to manipulate ice to freeze the Grimm, another with super speed to outrun them, etc.
One idea could be that your OC team is assigned a special mission to explore an ancient, forgotten ninja temple. Inside, they discover a powerful and dangerous jutsu that other villages are also after. Another is that they have to protect a visiting diplomat from another ninja village who has a secret that could change the balance of power in the ninja world.
Some 'oc on team 7 fanfiction' focuses on the OC being from a different village or culture. For instance, an OC from a water - based village that has unique fighting styles and traditions. When they join Team 7, they introduce new techniques like water - based jutsu that the others haven't seen before, which makes for really exciting storylines as the team has to adapt to this new element in their battles and training.
One interesting 'oc team 7 fanfiction' could be about an OC with a special power joining Team 7 on a mission to save a village from a powerful dark wizard. The OC's power might be something unique like the ability to control time briefly, which adds a new dynamic to the team's usual tactics.