Alright, so, theoretically. When Avengers Assemble Loki got swallowed by the All-Dark, it actually sent him to the end of time, kind of like when you get pruned or reset.
And what if King Loki somehow escaped him imprisonment in that pocket dimension-thing Agent of Asgard Loki put him in.
And so King Loki does something similar to the start of AoA, where instead he possesses AA Loki, and lives out as him back the Avengers Assemble universe, all while AA Loki is being forced to love through this nightmare world, kinda like the Hiimmarymary ARG if you've ever seen it. Wherein when he gets caught by whatever creatures are chasing him, he wakes up again, but it doesn't mean he didn't go through any pain.
Meanwhile, King Loki in his body isn't being subtle about the situation whatsoever, and the Avengers and co. Will have to try and save their Loki.
Maybe the Scarlet Witch could get involved, and they see what their Loki has to indure.
I'm also going to say that he was kinda controlled by the Eye of Agamotto at the end of S4, considering how much power it has, it prolly messed with him. And it doesn't mess with Strange or Spiderman cus the universe likes them, and as we know, the universe is always against Loki's.
Idk, I'm major brainstorming. Also, I believe that S5 of Avengers Assemble takes place in a different universe. (S1-4 Spiderman is Ultimate Spiderman, and I'm pretty sure S5 is 2017 Spiderman. The art style says so, at least. Haven't finished S5 yet.)