I tried Flawless widescreen and widescreen fixer.
Both seem to have problems.
Widescreen fixer doesn't maintains correct FOV during cutscenes as stated.
Edit game file, add keybind for your favoured fov. Cutscenes are designed for a specific fov, so don't expect them working as intended.
Try not to set it too high, otherwise you'll get a fish eye effect.
Don't mod your FOV in single player, though, it'll fuck up some cutscenes pretty badly.