Create NPC in Minecraft without Citizens Plugin?

I created a Minecraft Bukkit server on MC-Host24 a few days ago

for version 1.15.1.

I wanted to create NPC guards that guard certain parts of the map in front of players and or monsters. The Citizens plugin worked but no one knows a plugin with which I can create NPC for version 1.15.1.

If Citizens does not work yet, you have to wait until it is updated or go back to version 1.15. There's no other plugin and for watchers you still need denizen, but that also depends on citizens.