Buy from wherever and play together.
Age of Empires Definitive Edition

In another good move by Microsoft, the studio revealed today that there will be cross-play between the Steam and Microsoft Store versions of Age of Empires: Definitive Edition. This means that you and your friends can purchase the game from whichever store you want to and you'll be able to play together. Keep in mind that games appearing on both Steam the Microsoft Store can often be purchased from third-party sites without issue.

This news actually came the same day that the company announced that they're bringing even more of their first-party titles to Steam, including Gears 5. The company also revealed that they are again embracing Win32 applications for the Store instead of forcing UWP on users.

This confirmation of cross-play between these two PC storefronts was confirmed by the Age of Empires Twitter account.

Though not confirmed, this does give me some hope that future titles from Microsoft will feature this same sort of cross-play functionality. I have to imagine that Microsoft would ultimately like to get to the point where they can release a game on their Xbox platform, the Microsoft Store, and on Steam and have seamless cross-play between all three.

Age of Empires: Definitive Edition came out last year for the Microsoft Store. The release date for Steam has not yet been revealed. The release on Steam was only confirmed a few days ago.