Xavier Lopez

This plugin automatically logs in the user and redirects them to their profile when they register on BuddyBoss Platform.
Requirements: 
BuddyBoss Platform plugin must be active.

Auto Login on Register for BuddyBoss

Works well for me.

This plugin automatically logs in the user and redirects them to their profile when they register on BuddyBoss Platform.

duckinformatica

Loginner gives you automatic access to other WordPress backends you own, in one click. 
Every account is put in the admin bar for easy switching.
Easy customization of active accounts and user rights.
WARNING: THIS PLUGIN CAN BE INSECURE IF NOT USED CAUTIOUSLY. USE IT AT YOUR RISK!
For more informations: http://www.duckinformatica.it/prodotti-e-servizi/free-wordpress-plugins/
<h3>Upcoming features</h3>
<ul>
<li>Support other CMS: Joomla!, Drupal, etc.</li>
</ul>

Loginner

Loginner lets you open other Wordpress backends under your control in one click. WARNING: THIS PLUGIN CAN BE INSECURE IF NOT USED CAUTIOUSLY.

Auto Login on Register for BuddyBoss vs Loginner