The Green Goblin is one of the villains confirmed to return in Loki, but the MCU will go deeper into it in Spider-Man: No Way Home.
After Mysterio (Jake Gyllenhaal) exposed his identity to the world and framed him for his murder at villains from past Spider-Man movies will cross over to the MCU, and the ones confirmed are Doctor Octopus (Alfred Molina), Green Goblin (Willem Dafoe), Electro (Jamie Foxx), Sandman (Thomas Haden Church), and Lizard (Rhys Ifans).
The return of most of them was not only a surprise to fans of Spider-Man but was also quite confusing, as some of them died in their original movies, and the confusion only grew when Doctor Strange told Holland’s Peter that these villains are destined to die fighting their respective versions of Spider-Man. The first of these to be defeated by a Spider-Man was the Green Goblin, who was killed in Sam Raimi’s Spider-Man, which is why fans have wondered how he’s coming back in No Way Home – and the answer might be in his new costume, which s the theory of this Green Goblin not being the one seen in Raimi’s movie.
During a villains at CCXP, villains are variants of those seen in Raimi’s Spider-Man trilogy and Marc Webb’s The Amazing Spider-Man movies. Loki introduced the concept of variants, so it would make sense that the MCU carries on with it in No Way Home, which would also give more freedom to the writers as they don’t have to worry about continuity with the previous movies, so they don’t have to come up with convoluted and unbelievable explanations on why and how deceased villains are coming back.
With a just few more days to go before the release of Spider-Man: No Way Home, theories and rumors on the villains and the potential appearance of other characters (as are those of past versions of Spider-Man) will surely gain more force, but so far, the safest bet about the villains is that they are not the same ones seen in Raimi’s trilogy and Webb’s movies, and they just come from parallel sides of the still mysterious multiverse.