My preferred modding launcher is Mod Organizer 2. I love how I can easily see what files are overridden by each mod and better set the mod order.
To make life easier I've made:
GitHub - CramMods/modorganizer-game_crusaderkings3
Plugins for Mod Organizer 2 to support Crusader Kings III and Paradox mod archive installation.
Those ravenous ravenous rhinos.