To anyone here that follows MHA, I'm gonna sperg about this epiphany I just had today about what can be, in hindsight, the most convoluted reference to Star Wars.
If we're going to take into account Horikoshi's love for Star Wars and just how much he fucking references it, then AFO really could be Izuku's father, and that "Hisashi Midoriya" is simply an alias. This has been a common theory that's been repeated in the MHA community because, when you look closely into certain clues, it's there.
What makes this theory arguably feasible is Izuku having idolized All Might ever since he was a child. Bear with me here, because there are just so many coincidences for this to not be considered viable.
A Quirkless child not only idolizing Toshinori, but with a dedicated (near obsessive) dream of becoming a hero? Inko might even be Nana's daughter since Gran Torino mentioned that she gave up her "children", not child. Making Tomura Izuku's cousin.
It just came to me as an epiphany when I remembered AFO's remark that he always plans far ahead, to the point that any minor setbacks have little to no detriment to him.
He managed to locate Inko with his resources, having fabricated an entire background for himself and courted her. Unless this is a red herring, that's a pretty likely scenario since AFO could easily have donned a face with a shape shifting Quirk and made it seem like breathing fire was his main one. He simply chose Inko in the off chance that he'd get to use her against Nana.
After Izuku was born, and this is another theory that compliments this one, he may have had a Quirk. Whether it was similar to his uncle's or taken by AFO as a precaution, either one could be true, and so, he set the groundwork to enact his plan.
"Get close to the heroes". A post hypnotic suggestion. He exceeded that expectation by becoming Toshinori's protégé from either a twist of good luck or fate.
His love of archiving Quirks might even be part of that programming. An in-depth, encyclopedic knowledge and analysis of abilities, which is; also in hindsight, essential.
If any inkling of this theory is true, AFO might have just created a sleeper agent tailor made to infiltrate heroes and get close to Toshinori, but also someone who could get OFA so that he retrieve it at a penultimate time. Everything else with the League, Tomura, etc. That was all a front to his actual plan.
Izuku.