drush features-list-packages in drupal 8 doesn't include prefix
For configuration management in Drupal 8, you don't need to use features, you can use the configuration management module, which outputs .yml files.

The files are saved at sites/default/sync

to export them, use 

drush cex


(drush configuration export)

and to import them use

drush cim


You can also manually do this from /admin/config/development/configuration

See https://www.drupal.org/documentation/administer/config