Have a different issue? Join the Chaos Legion Modding Discord. The community is small, but passionate. We still can't fix the camera during the "Thanatos" boss fight, though. Some things are eternal.
The game's base FOV is for 4:3 (1.333:1). To convert to 16:9 (1.777:1), you multiply by 1.333 (which is 16/9 divided by 4/3). For 21:9, use 1.778 . The AutoFOV setting calculates this for you—try it first. chaos legion pc widescreen fix
If the fix came as a patcher application: Have a different issue