enZombies Traders v1.1
https://community.7daystodie.com/topic/24594-enzombies-more-zombie-variations/

This is an add-on mod that provides wandering traders using the UMA archetypes. These traders only provide ability to buy and sell goods, and do not give out quests. The main enZombies mod is required to be installed for these wandering traders to function. This traders mod is completely server-side, so only needed on the server.

Traders are invincible and so cannot be hurt or killed. To prevent traders from becoming zombie magnets and disrupt gameplay for zombie hordes, traders do not cause any damage when attacking. Instead, zombies are ragdolled a great distance away from trader when struck to allow zombie to go elsewhere and avoid attacking trader again. ** Alpha 21 will have new code that allows me to implement trader damage, death and despawning. Stay tuned. **

Version 1.1:
- fixed spawning issue that prevented other zombies from spawning