Originally posted by L1m3r:

Usually everyone needs to have the mods too. I recommend stuffing them in your personal modpack (just a 7z archive with everything required = bepinex, mods, configs).

If you use R2modman for installing and tweaking mods, you don't need to bother with making a modpack. You can share your profile code and other players just need to make a profile with your code. They will get all the mods you use + all the settings you changed.

@OP: having mods on the server requires a lot of work. If you don't have previous experience it would be the best that you find someone who will navigate you through the whole process. It will require a lot of your time, and every time you want to update mods or add another one you will need to go through the same process again.
As L1m3r suggested, maybe you should think about hosting it yourself rather than using gportal because it will be a lot easier to add/remove mods.
On my last modded server i spent more time tweaking and testing mods than actually playing the game. If you plan to combine Epic loot mod with some of Odin plus mods, you will definitely need some tweaking and testing.