Uninstallation

Check this article for a common actions list: https://nwdthemes.com/2016/07/12/magento-2-uninstall-module/

• remove the folder app/code/Nwdthemes/Powerbanners
• drop module tables from database

  DROP TABLE IF EXISTS `nwdthemes_powerbanners_style`;
  DROP TABLE IF EXISTS `nwdthemes_powerbanners_banner_store`;
  DROP TABLE IF EXISTS `nwdthemes_powerbanners_banner`;
  DROP TABLE IF EXISTS `nwdthemes_powerbanners_slider`;

• remove the config settings

  DELETE FROM core_config_data WHERE path LIKE 'nwdthemes_powerbanners%'

• remove the module from app/etc/config.php
• remove the module from database table setup_module

  DELETE FROM setup_module WHERE module='Nwdthemes_Powerbanners'

• flush cache

  php bin/magento cache:flush

• recompile code if you are in production mode

  php bin/magento setup:di:compile