<?php
class Prefix_Custom_Admin_Columns extends MB_Admin_Columns_Post {
    public function columns( $columns ) {
        $columns = parent::columns( $columns );
        /**
         * Add more column in a specific position
         *
         * @param string $position New column position. Empty to not specify the position. Could be 'before', 'after' or 'replace'
         * @param string $target The target column. Used with combination with $position
         */
        $this->add( $columns, 'col_category', 'Category', 'after', 'title' );
        $this->add( $columns, 'col_featured_image', 'Image', 'after', 'title' );
        return $columns;
    }

    public function show( $column, $post_id ) {
        switch ( $column ) {
            case 'col_featured_image':
//              the_post_thumbnail(array(70,70));
                echo get_the_post_thumbnail( $post_id, array( 70, 70 ) );
                break;
            case 'col_category':
                $terms = get_the_terms( $post_id, 'brand-category' );
                $terms = wp_list_pluck( $terms, 'name' );
                echo implode( ', ', $terms );
                break;
        }
    }
}

new Prefix_Custom_Admin_Columns( 'post', array() );