Fix available from the PC Gaming Wiki Community Files (search there).
The Game is VERT- out of the Box, you need to INI & HEX edit to get it HOR+
FOV INI edit: Go to --> Star Wars Jedi Knight II - Jedi Outcast\GameData\base and create a new text file called autoexec.cfg
and add this Lines in it:
seta r_customheight "1440" <-- your resolution height
seta r_customwidth "2560" <---- your resolution width
seta r_mode "-1" <--------------------- necessary for custom resolution
seta cg_fov "96.4" <------------------ can be changed to any value
Weapon FOVHEX edit: Go to --> Star Wars Jedi Knight II - Jedi Outcast\GameData\jk2gamex86.dll
Go to OFFSET 107480 and look for 00 00 A0 42 and change it to 00 00 FF 43 (this will break the wrong calculation of the Weapon SIZE and FOV)
I have the File in the Attachments: Jedi.Outcast - correct Weapon FOV.7z
All Values can be changed to your liking.
There is an annoying fault - when widescreen mode is enabled, the loading screens make your monitor display a solid white screen. And the rendered cutscenes are VERT-