Xenoblade Chronicles 3 has been updated to version 2.0.0, which enables support for the recently released Expansion Pass Vol. 4, here are the Patch Notes from Nintendo.
Additions to Spec
- Added functionality to receive Expansion Pass Wave 4.
- Fixed an issue where starting a NEW GAME after acquiring swimwear would make the player unable to receive the swimwear.
- In the event that this issue is already affecting your game, updating the title will cause the swimwear to already be acquired.
- Fixed an issue where a character’s status display in battle would remain the same as when interlinked.
Like with some updates on the Switch, you may need to check for it manually in order for it to download and install.