The series is confirmed to take place after Avengers: Endgame, which would make sense considering that Bucky has either been brainwashed or asleep in Wakanda for most of the MCU up until this point.
Spider-Man: Far From Home, the final movie of Phase 3, appeared to take place one year later in 2024.
After the events of Avengers: Endgame, the chronology of the Marvel Cinematic Universe may seem a bit confusing, considering that the movie ended in 2023.
Much like The Falcon and the Winter Soldier, WandaVision will also take place after Avengers: Endgame.