Email Redirect to Database setting for civicrm-settings.php?
Yes its possible to set Outbound email to 'Redirect to Database' by simply adding 2 lines in your civicrm.settings.php

global $civicrm_setting;
$civicrm_setting['Mailing Preferences']['mailing_backend']['outBound_option'] = 5;


Note: If global $civicrm_setting; is already present then no need to add it.