Either I don't see how to set this up or XF doesn't support it natively. If its the second perhaps there is an add-on solution and someone can point me to the correct resource.
What we have done for many years is put new registrations into a user group that needs moderation on all posts. We ask all new members to briefly introduce themselves in a "hello my name is" forum. Once they have done so a moderator moves them into "verified users".
Our moderators scan the forum daily and perhaps multiple times per day for new "hello my name is posts" Those new once in there get approved. Quality posts randomly within the forum get approved and often the user gets moved into the verified group that can freely post.
This probably turned away many new users from playing in the forum but it increased the quality of the forum as the once willing to jump through the hoops defiantly want to be part of it. It also keeps all the "buy gold" posts hidden from public view since they are flagged as "to be moderated". As a matter of fact my viewers have never seen a single spam post from a bot.
Can this be done with Xen?
User group option -> Moderate all posts - Not Set / Allow /Never