Pokémon Legends: Arceus has been updated to version 1.0.1 today by Nintendo. You can read the complete patch notes from here.
Based on the Japanese support website, this patch is mainly aimed at some bugs that have been fixed so the game is much better to play now. At least, this is what the translation from Japanese to English tells us, but if you want to go to the source, check the official website. The full patch notes can be read below.
Pokémon Legends: Arceus Update 1.0.1 Patch Notes
- Fixed some problems so that you can play the game comfortably.
