I reworked the zabbix module to use the new Zabbix 4.0 packages and mysql instead of postgres, it works on my raspberry in first tests. The only package needed from epel-pass1 is fping.
yum install --enablerepo=nethserver-testing,epel-pass1 https://mrmarkuz.goip.de/mirror/devtest/nethserver-zabbix-mysql-0.0.1-1.ns7.noarch.rpm