Well this could be about to get interesting, as The Pokémon Company have actually released a statement in regards to all the speculation about Palworld amid many claims of copying Pokémon's homework.
So far, there's no really solid proof that I can see of any actual direct copying (or of any AI use that people keep claiming too). There's a good few similarities to a few Pokémon, but lots of the examples people keep sharing around don't have me overly convinced.
Here's what The Pokémon Company said (source):
Inquiries Regarding Other Companies’ Games
We have received many inquiries regarding another company’s game released in January 2024. We have not granted any permission for the use of Pokémon intellectual property or assets in that game. We intend to investigate and take appropriate measures to address any acts that infringe on intellectual property rights related to the Pokémon. We will continue to cherish and nurture each and every Pokémon and its world, and work to bring the world together through Pokémon in the future.
The Pokémon Company
They didn't name Palworld directly, likely as that might put them in hot water if nothing comes of it.
Really, this reads a bit like a "please stop emailing us" statement. It was obvious they were going to look into it. Nintendo and The Pokémon Company are notoriously tough on taking action and they already started wiping traces of a Pokémon mod for Palworld. Even Nexus Mods have said they will not be hosting any such mods.
Again, they cannot take action just because it's a game that has monster catching in it. Pokémon don't own that idea, they can't. They could only take action for actual plagiarism. And as a whole, Palworld is actually objectively a very different game to anything Pokémon has put out.
In other news, Palworld crossed 8 million copies sold now.