Epic launches self-publishing tools, calls out Valve again: 'Steam has created a real problem for the industry'

pcgamer.com:

The Epic Games Store is now open for self-publishing. For $100, the same fee Valve charges for Steam submissions, anyone can submit a game for inclusion in the Epic Games Store library. Epic's system is similar to Steam Direct, which Valve introduced in 2018, and will probably result in Epic's library ballooning dramatically over the next year.

There are a few notable differences between Steam and Epic's self-publishing rules, however. In some ways, Epic's game submission guidelines(opens in new tab) are more permissive than Steam's, but Epic also has two big rules that Steam doesn't. Paraphrased, they are:

The first of those was expected: Epic CEO Tim Sweeney said in 2019 that the Epic Games Store won't sell porn, whereas Valve has allowed adult games on Steam since 2018—one of the store's most wishlisted games right now is an explicit sex game(opens in new tab). Before and even after making the decision to sell adult games, Valve has struggled with where to draw the line (one thing it currently prohibits is «sexually explicit images of real people») and Epic will likely have same issue: Is an erotic text adventure porn? How erotic is too erotic? Epic will have to decide.

The second of those rules is a requirement rather than a prohibition: If you release a multiplayer game on the Epic Games Store and Steam (or another PC store), you have to make it possible for everyone to play together, regardless of where they bought it. Epic offers a free solution for cross-launcher multiplayer called Epic Online Services, but says that developers can use their own online system if they prefer. 

Steam does not have such a requirement for multiplayer games, and its free multiplayer API, Steamworks, does not work on any store except