When you enter the world it would probably say the name and punch jam zombie jam haunted etc,

and if they turn it off you wouldn’t know unless you leave the world and enter so

my suggestion is that when they punch it off or on everyone in the world would be a message that says punch hammer turn off current world status(haunted zombie etc)

similar time the haunted indicator to the other suggestion, when all ghost are removed there will be an indication that shows that the mods are gone as well as the other mods of the world