https://www.pcgamer.com/epic-store-version-of-axiom-verge-briefly-crashed-because-it-was-missing-file-steamxnb/

The current free game on the Epic Games Store, Metroid-inspired platformer Axiom Verge, has been on Steam since 2015. But the Epic Store version was briefly missing a sound effect file named Steam, which caused it to crash when loading a new area. This didn't happen at the very beginning of the game, but was spotted by game developer Scott LaGrasta and confirmed by other Twitter users and posters on the Steam forums.

As with other Epic Store games that have had problems, users have turned to the Steam forums to post their issues, since Epic is missing features like support forums.