If I buy dying light 2 X/S optimized version of game can I gift it to someone who’s on...

That game will work on both the One and S/X, so yes.

Hello,

I hope you are doing well today. Welcome to the Xbox Community. Thank you for reaching out to Xbox Forums. Regarding Dying Light 2.

Dying Light 2 takes advantage of Smart Delivery and makes sure that you get the best available version for the console you’re playing on. If the Xbox Series X|S optimized version is available, that is the version that will be installed on your console. Even if you install Dying Light 2 on an external hard Drive using an Xbox One console, when you plug in the hard drive to a Series X| S, you will be prompted to upgrade your game to the series X|S version to ensure you have the best version possible for your device.

Thank you,

Smart delivery is the problem. Let Series X/S owners access Xbox One versions of games, so if a game like Dying Light 2 doesn't support cross gen play, we can still download a second version of the game and play with friends running the older version!

My friend (that plays on X-Box) gifted me dying light, and I tried redeeming it on my PC, but the game somehow got redeemed on my X-Box and now I can't download it on my PC without buying it again. What do I do?

Dying Light is only available on the Xbox from Microsoft Store which is why it got redeemed on your Xbox. If you want the PC version, you'd need to buy it from Steam, GOG or direct from techland (the Developer):

https://dl1.dyinglightgame.com/

Because on my Xbox series x, it only shows 'Optimized for series x/s' but if a xbox series x version of a game is NOT 'optimized' how would i know if I'm playing a series x/s version of a game?