To date, Game Freak and Nintendo have released two trailers for the upcoming Pokemon Scarlet and Violet. The first trailer revealed some of the returning Pokemon that will be featured in the new games while also revealing the starters, while the second Pokemon Scarlet and Violet trailer highlighted more of the new Generation 9 Pokemon and some of the games' features. Besides the fact that Pokemon Scarlet and Violet will be open world games, one of the most-talked about features in the new games is the ability to play in 4-player co-op.
Concrete details on Pokemon Scarlet and Violet 4-player co-op and how it works are unavailable at the time of this writing, but based on what was shown in the trailer, it seems players won't be tied down to their co-op partners and freely explore the game world. There may be restrictions on co-op that have yet to be revealed, but it seems pretty promising so far.
Rumor: Pokemon Scarlet and Violet Leak Shows Sprigatito's Final Evolution and Attack Animation
Pokemon Scarlet and Violet introducing proper co-op to the main series Pokemon games could have its advantages beyond simply letting Pokemon trainers play together. It will also make version exclusives much more interesting. For decades now, the only way Pokemon players were able to obtain version exclusive Pokemon was by trading them from one game to the other, and while that will presumably still be possible in the new games, co-op will potentially open the door for a new method of catching version exclusive Pokemon.
Barring any unannounced restrictions to the way co-op works, it seems as though Pokemon Scarlet and Violet players will be able to visit their friends in the other version and catch wild Pokemon. This is implied in the trailer
Read more on gamerant.com