@abiliomarques If you want to make some tests using FreeBSD, do not hesitate to give the experimental package a try :
How to ban user in a category or thread by category moderator?
I found only global moderator can ban user globally.
I don't really understand what you're asking. Yes, category moderators can't ban users globally AFAIK. This is expected behavior. Do you want them to be able to ban a user from a specific category?
yes, ban a user from a specific category or thread.