Two new trailers have dropped for Pokémon Brilliant Diamond & Shining Pearl, and Pokémon Legends: Arceus. The BDSP trailer (further below) confirms various features that also appeared in the original DS games, including the Pokétch, Amity Square and Poffins, but with some improvements (see below).
The L:A trailer reveals several new features including Noble Pokémon:
A new Pokémon was revealed - Kleavor - a Hisuian evolution
of Scyther. It is one of several Noble Pokémon
that have received a mysterious blessing, but something is causing them to become frenzied.