I don’t know how this game is coded and how mods work, but, if there’s at all time could you consider changing how mod loads happen in the game?
In the other major survival game I play (Don’t Starve Together) the mods for each server are saved and loaded automatically so that you can try out new servers, new places, etc. I find that I’m not willing to join another server other than playing by myself because I don’t want to forget what the load order was for my server and forget when changing it back and then have to go through the files, or then look up what another server’s load order was.
Changing mods, fixing the order, logging out, logging back to check order, and maybe logging out, logging back and then logging in… it’s a lot. Certainly it’s enough of a deterrent that I haven’t bothered much playing with others for very long as the mod load consideration similarity to my personal mod load is a big factor.
They are already working on this. The last update about it was yesterday in their Q & A. I time stamped it in the write up I wrote, which can be found here.
Further, you can already do what you desire if you know how to use Windows File Explorer. While you currently have to manually download every mod, you can create multiple sets of modlists very easily.
Just navigate to steamapps\common\Conan Exiles\ConanSandbox\Mods and locate your modlist.txt and create a copy. Now, anything not named EXACTLY modlist.txt will not be used. So you could have a modlist_single_player.txt, modlist_cool_server.txt, modlist_friends_server.txt, etc. Then, whatever game you are going to join, just change the name of the modlist that you want to use to modlist.txt and the game will use that one.
Then, when you start the game, you don’t have to even click on the mod load order in-game at all, it’s all driven by the modlist.txt No restarting of the game is required.
Further, somebody made a 3rd party utility that makes this process easier too, which utilizes collections on steam. That can be found here.