I have been playing and modding skyrim classic (oldrim is slang name for it) for years now at 6040 x 1080. Oldrim works with flawless widescreen, but not special edition. There is a mod out there for SE that does allow for 5760 x 1080 you mentioned above, but I couldnt get SKSE to work for it. Anyway here are my tips to get started:
in skyrimprefs.ini - under [Display] set iSize H=1080
iSize W=6040 (use whatver your bezel compensated resolution is here of coarse)
in enblocal.ini (should be in your main skyrim file where TESV.exe is located) - set [WINDOW]
ForceBorderless=True
ForceBorderlessFullscreen=True
Do not use NMN Organizer it sux. Only Mod with Mod Organizer. Links to get started on modding that are really helpful
Start with This!!!!!!!!
https://www.reddit.com/r/skyrimmods/wik ... ners_guideMany Great Mods that are hard to live without
https://www.reddit.com/r/skyrimmods/wiki/essential_modsThese STEP project pages:
https://wiki.step-project.com/Guide:SkyrimPrefs_INIhttps://wiki.step-project.com/Guide:Skyrim_INIhttps://wiki.step-project.com/Guide:ENBlocal_INIStart there. The mod OneTweak will take over duty for fullscreening ultrawide once you have MO working
https://www.nexusmods.com/skyrim/mods/40706/Message me if you have any questions, but I swear that beginners guide will easily get you stated with no fuss. If you get into modding, it has a steep learning curve, but is so awesome once you do.