Well, you could have a scenario where the main characters from AOT are reincarnated in our world. Eren, for example, could be a normal high - school student but start having strange dreams about his past life as a Titan shifter. Mikasa and Armin could also be reborn, and they gradually discover their past identities and the threat of Titans that might still lurk in some form in this world.
One idea could be that the Titans suddenly appear in modern cities. People have to quickly adapt their defense mechanisms, like using modern military equipment against them. Another could be that the Survey Corps' technology is somehow transferred to our world, and we see how modern scientists study and improve it.
Maybe in the 'AOT in our world' fanfic, the Walls from the AOT world are magically created around certain parts of our world. The people inside these Walls live in a state of fear, not knowing what's outside. And a group of brave individuals, inspired by the Survey Corps, decide to explore beyond the Walls to find out if there are any Titans and, more importantly, if there's a way to break free from this new confinement.
Chapter 431, "Su Yinwan Is Here Too?!", is the clearest early answer because it turns Shang Shaojing's situation into a concrete plot event. The chapter gives readers a real answer by opening on [Holy shit, why is Su Yinwan on this show too???] [!!! and ending on Is the program team this cruel?.
Chapter 343, "He Can Support Jiang Li for a Lifetime", is the clearest early answer because it turns Jiang Li's situation into a concrete plot event. The chapter turns that into something concrete by moving from But she suddenly acted mischievously indifferent, "Are you a...
Chapter 153, "Word Spreads, Director Sun Takes the Lead in Shipping the CP!", is the clearest early answer because it turns Lai Fu's situation into a concrete plot event. Early on, Wisps of smoke gradually rose from the small kitchen..
Chapter 150, "Has She Been Cursed?!", is the clearest early answer because it turns Film Festival's situation into a concrete plot event. Early on, Upon hearing the first part of Jiang Li's words, Zhang Cheng.... By the end, He spent the last few days visiting various renowned doctors, while....
Chapter 113, "Morning Exercise Check-in Group!", is the clearest early answer because it turns Jiang Shixu's situation into a concrete plot event. The setup is The next day, Jiang Lili was up before dawn as usual., but the pressure keeps building through But this time was different;
Chapter 439, "Never Question Sister Li", is the clearest early answer because it turns Yu Li's situation into a concrete plot event. It opens with There was no helping it, she brought the man here, so even if he was...
Chapter 223, "Pigpen Live Stream", is the clearest early answer because it turns Shang Shaojing's situation into a concrete plot event. It opens with So, for the first time, Jiang Yan, who had always styled himself as... and closes on The damned Jiang Li was tricking him again!.
Chapter 188, "First in Grade, It Can Only Be Me, Jiang Cheng", is the clearest early answer because it turns Jiang Li's situation into a concrete plot event.
Chapter 47, "This Result Definitely Has Insiders!", is the clearest early answer because it turns Flash Change's situation into a concrete plot event. The chapter gives readers a real answer by opening on Qi is actually second???] [Did the production team make a mistake?
Chapter 424, "He Must Be Very Strong", is the clearest early answer because it turns Ji Yanbai's situation into a concrete plot event. The chapter turns that into something concrete by moving from Shh!" Jiang Yan, who was leading the group, turned around and made a...