Customize WooCommerce Categories & Tags Label

functions1a.php

/* Customize Product Categories Labels */
add_filter( 'woocommerce_taxonomy_args_product_cat', 'custom_wc_taxonomy_args_product_cat' );
function custom_wc_taxonomy_args_product_cat( $args ) {
	$args['label'] = __( 'Product Categories', 'woocommerce' );
	$args['labels'] = array(
        'name' 				=> __( 'Product Categories', 'woocommerce' ),
        'singular_name' 	=> __( 'Product Category', 'woocommerce' ),
        'menu_name'			=> _x( 'Categories', 'Admin menu name', 'woocommerce' ),
        'search_items' 		=> __( 'Search Product Categories', 'woocommerce' ),
        'all_items' 		=> __( 'All Product Categories', 'woocommerce' ),
        'parent_item' 		=> __( 'Parent Product Category', 'woocommerce' ),
        'parent_item_colon' => __( 'Parent Product Category:', 'woocommerce' ),
        'edit_item' 		=> __( 'Edit Product Category', 'woocommerce' ),
        'update_item' 		=> __( 'Update Product Category', 'woocommerce' ),
        'add_new_item' 		=> __( 'Add New Product Category', 'woocommerce' ),
        'new_item_name' 	=> __( 'New Product Category Name', 'woocommerce' )
	);

	return $args;
}

functions1b.php

add_filter( 'woocommerce_taxonomy_args_product_cat', 'custom_wc_taxonomy_label_product_cat' );
function custom_wc_taxonomy_label_product_cat( $args ) {
	$args['label'] = 'My Categories';
	$args['labels'] = array(
        'name' 				=> 'My Categories',
        'singular_name' 	=> 'My Categories',
        'menu_name'			=> 'My Categories'
	);

	return $args;
}

functions1c.php

add_action( 'init', 'custom_wc_product_cat_label' );
function custom_wc_product_cat_label() {
    global $wp_taxonomies;

    if ( isset( $wp_taxonomies['product_cat'] ) ) {
	    $cat = $wp_taxonomies['product_cat'];
	    $cat->label = 'My Categories';
	    $cat->labels->singular_name = 'My Category';
	    $cat->labels->name = $cat->label;
	    $cat->labels->menu_name = $cat->label;
	}

}

functions2a.php

/* Customize Product Tags Labels */
add_filter( 'woocommerce_taxonomy_args_product_tag', 'custom_wc_taxonomy_args_product_tag' );
function custom_wc_taxonomy_args_product_tag( $args ) {
	$args['label'] = __( 'Product Tags', 'woocommerce' );
	$args['labels'] = array(
	    'name' 				=> __( 'Product Tags', 'woocommerce' ),
	    'singular_name' 	=> __( 'Product Tag', 'woocommerce' ),
        'menu_name'			=> _x( 'Tags', 'Admin menu name', 'woocommerce' ),
	    'search_items' 		=> __( 'Search Product Tags', 'woocommerce' ),
	    'all_items' 		=> __( 'All Product Tags', 'woocommerce' ),
	    'parent_item' 		=> __( 'Parent Product Tag', 'woocommerce' ),
	    'parent_item_colon' => __( 'Parent Product Tag:', 'woocommerce' ),
	    'edit_item' 		=> __( 'Edit Product Tag', 'woocommerce' ),
	    'update_item' 		=> __( 'Update Product Tag', 'woocommerce' ),
	    'add_new_item' 		=> __( 'Add New Product Tag', 'woocommerce' ),
	    'new_item_name' 	=> __( 'New Product Tag Name', 'woocommerce' )
	);

	return $args;
}

functions2b.php

add_filter( 'woocommerce_taxonomy_args_product_tag', 'custom_wc_taxonomy_label_product_tag' );
function custom_wc_taxonomy_label_product_tag( $args ) {
	$args['label'] = 'My Tag';
	$args['labels'] = array(
	    'name' 				=> 'My Tag',
	    'singular_name' 	=> 'My Tag',
        'menu_name'			=> 'My Tag'
	);

	return $args;
}

functions2c.php

add_action( 'init', 'custom_wc_product_tag_label' );
function custom_wc_product_tag_label() {
    global $wp_taxonomies;

    if ( isset( $wp_taxonomies['product_tag'] ) ) {
	    $cat = $wp_taxonomies['product_tag'];
	    $cat->label = 'My Tag';
	    $cat->labels->singular_name = 'My Tag';
	    $cat->labels->name = $cat->label;
	    $cat->labels->menu_name = $cat->label;
	}

}

Fantastic! I use the functions1a.php and work great in the back end. It's possible that it works in the front end too?.
I use a plugin for make some ajax filters to products and they don't change the name at the title. Many thanks.
Perhaps I need to translate some more label?

I found it!

add_filter(  'gettext',  'change_post_to_myname'  );
add_filter(  'ngettext',  'change_post_to_myname'  );

function change_post_to_myname( $translated ) {
     $translated = str_ireplace(  'Categories',  'My New Name' ,  $translated );  // ireplace is PHP5 only
     return $translated;
}