First thing first. It's "Jedi Knight: outcast 2" I'm talking about.
ad 1. In academy mod ( https://mrwonko.de/jk3files/Jedi Outcast/Mods/Multiplayer/26155/ ) there is command that allow you to spawn NPC on a server (you need devmapall) /g2animent to spawn a NPC (description in readme file in mode pack).
ad 2. "npc that would be able to use lightsaber not only hold a hilt" by that I mean that you can spawn NPC with lightsaber but the NPC is just hold the hilt and do nothing (when you give him a weapon he can walk/run, shoot)
ad 3. PhatMOD (1.0) ( https://mrwonko.de/jk3fil