No, Hogwarts Legacy does not have multiplayer at launch. It is a strictly single-player experience with no online multiplayer features or co-op.
This has been confirmed by the official Hogwarts Legacy FAQ page. It clearly states that Hogwarts Legacy will not allow players to play together.
However, while it doesn’t have any official multiplayer, a fan-made mod from the creators of Skyrim Together is launching soon that adds multiplayer to Hogwarts Legacy.
Of course, even without the mod, you won’t be alone while exploring Hogwarts. There are a plethora of companions in Hogwarts Legacy for you to interact with.
While it is unsurprising that Hogwarts Legacy will not have online multiplayer at launch, it makes sense considering the developer’s level of expertise and the scale of the project.
Fans looking for a GTA Online-type of experience in Hogwarts Legacy will be sorely disappointed. Nevertheless, a multiplayer mode could be added in the future.

Will Hogwarts Legacy Get Multiplayer in the Future?
While nothing has been confirmed, developers Avalanche Software and Warner Bros Games have avoided saying that multiplayer will never appear.
It is possible that Hogwarts Legacy could have multiplayer in the future. After all, the success of other open-world titles transitioning into online multiplayer such as GTA Online, has paved the way.
Exploring Hogwarts Legacy’s surprisingly enormous open world with a friend and uncovering all of the iconic locations and hidden secrets together is surely high on every Harry Potter fan’s bucket list.
Additionally, in an interview with Press Start, Hogwarts Legacy’s Technical Game Designer, Stephen Dona implied that multiplayer could be added in the future.
He stated that while he wanted to avoid giving away future plans, “right now [Hogwarts Legacy] is a single-player game.”
Without speculating too much, “right now” certainly doesn’t rule out the possibility of multiplayer being added in the future.

In the meantime, there are a shocking amount of side quests to complete in Hogwarts Legacy. Some are even longer than the main quests!
You should also unlock all of the free outfits and rewards in Hogwarts Legacy before jumping in so you can explore the Wizarding World in style.
Is Hogwarts Legacy Cross-Platform?
No, because Hogwarts Legacy is a single-player-only experience with no online or multiplayer functionality, it is not cross-platform.
The developers of Hogwarts Legacy have also not confirmed whether you can carry over your save from one platform to another. However, as of right now, it seems unlikely that you will be able to.
It is possible that this will change if multiplayer features are introduced in the future. However, right now, fans should not expect cross-play features between platforms.