Yes, Sea of Thieves supports Cross Platform between Windows 11, 10, Xbox and Steam version of PC.
How to Enable Sea of Thieves Cross Platform?
The Sea of Thieves Crossplay is enabled by default
And to check that you just need to invite your friends and start the game
How to Disable Sea of Thieves Cross Platform?
Here's how to disable Sea of Thieves cross platform: 1. Go to Xbox settings and then to Accounts.2. Now select Privacy and Online Safety 3. Then choose the Xbox Live Privacy option > View Details & Customize
4. And in the Communications and Multiplayer option, you will be able to turn off cross-play for Sea of Thieves.