Register taxonomies using Extended Taxos library https://github.com/johnbillion/extended-taxos

taxonomies.php

/**
 * ============================================================================
 * TAXONOMIES
 * ============================================================================
 */

$args = array(
    'labels' => array(
        'add_new_item' => __('Add New Category', 'wip')
    )
);

$labels = array(
    'plural' => __('Categories', 'wip'),
    'singular_name' => __('Category', 'wip'),
    'slug' => 'location-categories'
);

register_extended_taxonomy( 'location_cat', 'location', $args, $labels );