Snippet to hide duplicate shipping rates (Name and Cost both should match) for PluginHive WooCommerce Shipping Plugins - https://www.pluginhive.com/product/multiple-carrier-shipping-plugin-woocommerce/, https://www.pluginhive.com/product/woocommerce-ups-shipping-plugin-with-print-label/, https://www.pluginhive.com/product/woocommerce-fedex-shipp…

functions.php

/**
 * Snippet to hide duplicate shipping rates (Name and Cost both should match).
 * Created at : 09 Aug 2018
 * Updated at : 09 Aug 2018
 * PluginHive Plugins : https://www.pluginhive.com/plugins/
 * Gist Link : https://gist.github.com/xadapter/71473722eb88105bf70d6d5d0932aed1
 */
add_filter( 'woocommerce_package_rates', function( $shipping_rates ){

	$hide_duplicate_rules = array('wf_multi_carrier_shipping');		// Hide Duplicate Rates for these shipping methods

	$rates_to_check = array();
	foreach( $shipping_rates as $key => $shipping_rate ) {
		$method_id = $shipping_rate->get_method_id();
		if( in_array( $method_id, $hide_duplicate_rules ) ) {
			$rates_to_check[$method_id][$key] = array(
				'label'	=>	$shipping_rate->get_label(),
				'cost'	=>	$shipping_rate->get_cost(),
			);
		}
	}
	if( ! empty($rates_to_check) ) {
		foreach( $rates_to_check as $rates_of_particular_service ) {
			$array_keys_before_uniqueness = array_keys($rates_of_particular_service);
			$unique_array = array_unique( $rates_of_particular_service, SORT_REGULAR );
			$unique_array_keys = array_keys($unique_array);
			$shipping_ids_to_unset = array_diff( $array_keys_before_uniqueness, $unique_array_keys );
			foreach( $shipping_ids_to_unset as $key ) {
				unset( $shipping_rates[$key]);
			}
		}
	}
	return $shipping_rates;
});