@Sjd6795 Hi
Regarding the Npc attack against other Npcs that appear using the NpcSpawn plugin, there is a parameter
internal bool CanTargetOtherNpc = false;
in the NpcSpawn plugin that needs to be done with the value true. I also saw that you say that this may not have helped you, then most likely there is some other plugin that blocks their attack, perhaps some kind of plugin conflict will be written in the console, it's worth paying attention to this. Also I didn't quite understand if zombies from ZombieHorde attack NPCs from NpcSpawn or not?
Regarding the fact that the NPCs do not go into sleep mode, you can also change the parameter
["CanSleep"] = true,
in the BetterNpc plugin to false, in the next update of the plugin, this parameter will be in the plugin configuration