WP Mega Menu Pro is a Premium WordPress plugin, where you can easily add widgets in a single or multiple group wise. You can assign specific column to specific group if you selected multiple type group for mega menu. This plugin includes both horizontal as well as vertical mega menu, it is a built in visual mega menu builder plugin with features to display menu as flyout or megamenu type with orientation as vertical or horizontal type.
Demo: https://codecanyon.net/item/wp-mega-menu-pro-responsive-mega-menu-plugin-for-wordpress/19190840