The biggest reason James Wan's The Conjuring Universe was able to spin-off into several different in-universe franchise was the introduction of the Warren's occult museum, which contains all sorts of haunted/possessed artifacts, each with their own backstory ripe for adaptation.
With the release of the third Annabelle film, Annabelle Comes Home, the story returns to the aforementioned museum, allowing the filmmakers to explore even more potential spin-offs.
The newest trailer shows off some of the evil entities who may very well received their own film, most prominently "The Ferryman" (pictured below), who could be the centerpiece of the film, much like The Crooked Man in The Conjuring 2. We've also seen teases of a demonic toy monkey, a samurai, and even a demonic werewolf.
One thing we know for sure is that the table is certainly being set for many more future spin-offs.
Gary Dauberman, the screenwriter of the Annabelle films, IT and The Nun, makes his directorial debut on the film, which is produced by Wan and Peter Safran (Aquaman), who has produced all the films in The Conjuring franchise.
"Determined to keep Annabelle from wreaking more havoc, demonologists Ed and Lorraine Warren bring the possessed doll to the locked artifacts room in their home, placing her “safely” behind sacred glass and enlisting a priest’s holy blessing. But an unholy night of horror awaits as Annabelle awakens the evil spirits in the room, who all set their sights on a new target—the Warrens’ ten-year-old daughter, Judy, and her friends."
The film stars McKenna Grace (“The Haunting of Hill House") as Judy; Madison Iseman (Goosebumps 2: Haunted Halloween) as her babysitter, Mary Ellen; and Katie Sarife (“Supernatural”) as troubled friend Daniela; with Patrick Wilson (The Conjuring and Insidious films) and Vera Farmiga (The Conjuring films, Godzilla: King of the Monsters) reprising their roles as Ed and Lorraine Warren.
Dauberman directed the film from a screenplay he wrote, from a story by Dauberman and Wan. Richard Brener, Dave Neustadter, Victoria Palmeri, Michael Clear, Michelle Morrissey and Judson Scott served as executive producers.
Annabelle Comes Home on June 26th, 2019.