You will have to write some

badlop — Mon, 12 Jun 2017 10:26:04 +0000

You will have to write some source code. Reading what you want, I think the most similar module is mod_logsession, that is included in ejabberd-contrib git repository. You could first modify it to log the successful connection/disconnections. And later modify it to do what you want it to do.

ejabberd - Comments for "How to notification regarding change in connection of client"

You will have to write some