Sony's Venom may not appear in the Marvel Cinematic Universe, however it seems like the Symbiote while share the same reality as Tom Holland's Spider-Man and the other superheroes in Marvel's cinematic franchise.
Speaking in an interview with Fandom to discuss the upcoming Spider-Man movie, Homecoming, Sony producer Amy Pascal clears up the confusion regarding Venom's place in the Marvel Cinematic Universe.
"First, there is Spider-Man happily in the place where he's supposed to be which is in the Marvel Universe. I think everything comes from that. This is the signpost, the tentpole, the signature and… the other movies that Sony's going to make, in their relationship to this [MCU] Spider-Man, take place in this [separate Sony] world. Although you're not going to see them in the Marvel Universe, it's in the same reality."
Feige had also been present during the interview and confirmed his Spider-Man: Homecoming co-producer's response, saying that it was "the perfect answer." Right now it looks like the official arrangement between Marvel and Sony only consists of the use of Spider-Man, and not the other characters associated with the webslinger. The two may still be working out the kinks of their arrangement further, and this "reality"-sharing gives them time to see how far they can take their partnership in the future.
Spider-Man: Homecoming hits the big screen on July 7, 2017. Venom releases on October 5, 2018.