https://wccftech.com/epic-online-services-pc-crossplay-unites-steam-and-epic-games-store-communities/

The Epic Online Services crossplay development tool has been updated to seamlessly support Steam and Epic Games Store communities on PC.

Epic is also working on adding support for more PC stores, macOS and Linux, and even console and mobile platforms. As a reminder, Epic Online Services is not restricted to the Unreal Engine and can be used with any engine, store, or platform.