According to several sources that have previously revealed news about Nintendo and Pokémon, as well as Pokémon Legends: Z-A, the next Direct includes the announcement of a new "spin-off." This will probably not surprise fans, given the long history of Pokémon spin-offs.
Sources do not specify whether it will be a new Pokkén, Pokémon Mystery Dungeon, Pokémon Rangers, Pokémon Stadium, Pokémon Colosseum, or Snap - it is only known that they will present a project outside the main series.
For several weeks in a row, unofficial sources have been reporting about a new Direct in September, but there is no official confirmation yet.