As of right now, the next entry in The Conjuring universe is Corin Hardy’s The Nun — which will center on the demonic Valak entity introduced during the events of The Conjuring 2.
The film stars Taissa Farmiga (the sister of The Conjuring’s Vera Farmiga) and Alien: Covenant’s Damian Bichir, and is the only upcoming Conjuring film with a set release date.
In terms of chronology, The Nun will be the first film on The Conjuring timeline (reportedly taking place sometime in the 1940s or 1950s), and it will center on a priest who travels to Rome to investigate the mysterious death of a nun.