Non of those methods tell him to care about that simple rule.

Broski, of COURSE non-Workshop addons don't go into the "workshop" folder! There is a README.txt in that folder that tell you that mods go there

I don't even know what "different methods" you possibly could have tried.

i've been looking for several methods to put mods outside workshop and I finally learned how to work from you, i'm very thankful !

Put the mod in "addons" folder, not "workshop" folder.
"addons" contains all mod including those that aren't downloaded by subscribing.
"workshop" only contain those that you get by subscribing. They have their thumbnail, description, title, and link to workshop page. Therefore it is recognized separately from those that aren't from workshop.

i've unsubscribed all mods, I've reinstalled the mods, I've tried several methods, but with no results, I think there's an error but I have no idea, so I've recorded it to see if i've made a mistake
https://www.youtube.com/watch?v=PFQD3SkdZWk

Assuming i have a file .ani separated. But for some reason i want to edit it a bit (reason: port to different model e.g. mp5 to ump45 ; port to different weapon slot; replace anim of sequence(s); or just simply change fps or fadein/fadeout value), so everytime i do i must submit my edited .ani to workshop (people get to choose). This situation, at some point, is just as good as having animation and model compiled into one like how it is now.

Also they never thought modding community would grow this much.

Splitting the animations and models doesn't break anything though because existing weapons still have all their animations built in and they don't include the new anim file, it would have served as nothing more than a modders resource, there wouldn't have been any need for standardisation or coordination, if a modder was to try and attempt the same actions though it would require coordination between modders to get their actual userbases to subscribe to the neccesary addons/assets which I believe only someone like xdshot could pull off with something akin to XDR but for weapons. TLS being an update that everyone received and both modders and users could have readily taken advantage of. It would've taken them all of 30 minutes to seperate the anims from the weapons but they didn't because there were no good ideas behind TLS update.

As in, it should have been done this way on release, and not in a community update that someone maybe, possibly will find useful, and use maybe two times and abandon the idea entirely. People had complained even about the additional weapon skins.

That would require a lot of standardization and coordination between creators, something that's either almost impossible or not worth it given the game's already past a decade of modding.

Bro, real talk though, if the TLS team weren't such chumps they literally would've separated the weapon animations and model files, it wouldn't have created any issues for existing mods and it would've been great for modding support, but God forbid they do anything to actually benefit modders.