This is what we had folks do on a forum I was running in the past: How to enable your community to use Discourse as a (micro) blogging platform
It requires allowing users to create new tags, but otherwise doesn’t strictly require any plugins.
That said, it is easy for folks to do things “wrong” and so some mixed results may be expected without moderator intervention.
Perhaps it is a reasonable starting point though, even if you do determine a plugin is needed. There are a handful of other topics linked to that one that may be of interest as well.