XBox Series X Digital Edition?

I’m confused how will it work for both if one is physical and the other is digital

Both consoles are digital...it's just the Series S is Digital only whereas the Series X is both Digital and Physical.

75th Anniversary Edition Pre-Order can be downloaded to the Series S, the Series X and the Xbox One

The Hogwarts Legacy Deluxe Edition (at least the digital version) contains both the Xbox Series X/S version and the Xbox One version.

This is the page that the Official Website links to for Xbox:

https://www.xbox.com/en-GB/games/store/hogwarts-legacy-digital-deluxe-edition/

And, it states:

"Xbox One and Xbox Series X|S Digital Versions"

Bear in mind that the Xbox One version of the game doesn't release until April 4th so it will show as only available for Series S/X until that time

That edition of the game contains both Xbox One and Series X/S versions:

"Xbox One and Xbox Series X|S Digital Versions"

https://www.xbox.com/en-US/games/store/hogwarts-legacy-digital-deluxe-edition/

However, you won't be able to play on Xbox One till April 4th when the Xbox One version is released

You have names mixed up. There are no consoles named the Xbox One Series S or Xbox One Series X.

The Xbox One/One S/One X all have a disc drive.

The Xbox One S All Digital Edition does not have a disc drive.

The Xbox Series X has a disc drive.

The Xbox Series S does not have a disc drive.

All the consoles can play backward compatible games. The Series S and One S all digital edition can only play games digitally downloaded.

The other consoles can play games from disc and from digitally downloaded,

I hope this clears things up for you.

The digital deluxe edition will only work on the Series S/X. You would need to buy the Xbox One version of the game.