Disable MiniPigmans

So i’m currently running a ftb ultimate reloaded server for me and my friends.
Got a mob drop tower built and running with pigmans, problem is that there are spawning mini zombie pigmans on chickens that won’t die from fall damage.
I’m searching for Plugins or any other solutions to prevent either chickens or minipigmans from spawning.
Read about ProjectWorlds but cant find the command for that, because it’s kinda badly explained how to use it as a noob like me xD

Ty for the help