[Closed] On register require admin approval
User registration is being processed through default WordPress registration system. If you already have a registration approval function in WP then it'll work for wpForo. If you don't have such function please search for Registration activation plugins, they should work for wpForo too. These are two good examples:
please contact to those plugin support or try others, there dozens of solution for this in WordPress plugin directory. We only support wpForo plugin related issues.
The both are good, just try and find the best for you. Also you can search for other similar plugins in wordpress.org plugin directory.