Can I play Pokemon sword with someone who has Pokemon shield?

Can you clarify for me, are you wondering if it's possible to play Pokemon Sword with someone who owns Pokemon Shield as if they were playing the same game, or are you asking if there's some kind of cross-compatibility feature between the two games? If it's the former, it's important to note that while Pokemon Sword and Shield are part of the same series and share many similarities, they are separate games with their own unique features and Pokemon. However, there is a way to play with friends who have the other game through the use of online multiplayer features, such as the Y-Comm feature, which allows players to connect with others and participate in various activities together, including trading Pokemon and battling. So, in a sense, you can still enjoy the Pokemon experience with friends who own the other game, but it won't be exactly the same as if you were both playing the same game.