So the mod either changes the PVE Server to a PVP Server or the zones from the mod are PVE as well. We practically tried every setting and we have no clue why it is not working. If there is something we have overseen, a small hint would be appreciated. Thanks in advance

If you are trying to make a PVE Server with PVP zones you need to have TruePVE installed. When this is activated by default, this will add whatever monuments you enable into the list to be excluded from the TruePVE rules and makes those zones PVP, This requires Zone Manager in order to function as well.

Hm okay we tried that, but surprise something is just wrong with our setup.
This is our mod collection, could there be a problem with any other mod we use or is something wrong about our files from just seeing the names?

Would need to see the configs for both TruePVE and Zone Manager Auto Zones.

Okay here is the TruePVE:
https://1drv.ms/u/s!Amw71vHuL__deM7UHt1uAXTaBCw
And here is the ZoneManagerAutoZones:
https://1drv.ms/u/s!Amw71vHuL__deQJZUCK12AP3ny4
Thanks a lot!

Merged post

In case the links dont work:
TruePVP:
https://pastebin.com/djaDeN2X
ZoneManagerAutoZones:
https://pastebin.com/qc2mZXGH

I see why its not working for you
Zone Manager Auto Zones you have this set to false when you have TruePVE

"Enable TruePVE to allow Rule Sets": false, <= that should be true with out this it has no way to add it to your TruePVE config to exclude these zones from any PVE to turn them into PVP Zones.