Fallout New Vegas
Fallout: New Vegas will not launch unless a specific registry key exists. To run the game simply create an empty key in HKEY_CLASSES_ROOT via the registry editor and name it com.epicgames.launcher. Below you'll find various methods.
Download this file: https://legendary.gl/assets/fnv_fix.reg, then double-click it and confirm to update the registry.
Run the following in a command line running as administrator (right click -> run as administrator):
reg add HKCR\com.epicgames.launcherRun the following command inside the used Wine prefix:
wine reg add HKCR\\com.epicgames.launcherOpen regedit and create a key like so:
On Linux/macOS: run wine regedit inside the used Wine prefix to.