Well, in fanfiction the outcome can be very different based on various factors. Superman is known for his superhuman strength that can move planets, his invulnerability which makes him hard to harm, and his speed which is faster than light. Thanos is a powerful villain with great strength and the Infinity Stones at his disposal. However, in many fanfictions, Superman's powers are often portrayed as being more than a match for Thanos. His ability to soak up energy, like sunlight, gives him a constant source of power. Also, his moral code might make him more determined to win in a fight against a villain like Thanos. So, generally speaking, Superman has a good chance of winning in fanfiction battles against Thanos.
Thanos could also win in a fanfiction. He has incredible strength and the power of the Infinity Stones at his disposal. In a lot of fanfictions, the power levels are often exaggerated. Thanos could simply use the Reality Stone to make Iron Man's weapons ineffective or use the Time Stone to freeze Iron Man in time and then defeat him. His brute strength alone is enough to overpower Iron Man in a direct confrontation. And his experience in battles across the universe gives him an advantage over Iron Man who mainly operates on Earth.
Well, Naruto has his powerful jutsus like the Rasengan and Sage Mode. Thanos, on the other hand, is super strong and has the Infinity Stones. But in fanfiction, it could go either way. Maybe Naruto could use his shadow clones to overwhelm Thanos and then hit him with a super - powered Rasengan. However, Thanos could use the Infinity Stones to turn Naruto's attacks against him. It really depends on how the writer of the fanfiction wants to portray the battle.
In fanfiction, it could go either way. Batman is known for his strategic mind and vast array of gadgets. He could potentially find a way to outwit Thanos. However, Thanos is extremely powerful with his strength and the Infinity Stones. If Batman could somehow get his hands on one of the Stones and use it against Thanos, he might have a chance. But overall, Thanos' raw power gives him an edge most of the time.
Superman is extremely powerful on his own. His powers are almost god - like. But the Avengers have a lot going for them too. For example, Iron Man has his high - tech suits which can adapt to different threats. Captain America is a great strategist. In a fanfiction, it could depend on the circumstances. If it's a fight in an environment full of kryptonite, the Avengers would have an advantage. But in a normal battle, Superman's power might be too much for the Avengers to handle all at once.
Well, in fanfiction, it could really go either way. Harry Potter has his powerful magic like the Patronus charm and the Killing Curse. But Thanos is super strong and has the Infinity Stones. If Harry could somehow get his hands on the Time Stone, he might be able to outwit Thanos. However, Thanos' brute strength and combat experience can't be underestimated.