Change specific payment gateway title in WooCommerce

I need to change the Woocommerce payment gateway names, not the ones hat are displayed on the frontend(this can easily be achieved in the settings) but the inernatl titles Woo is using.

In class-wc-gateway-cheque.php for example I found this

        $this->id  = 'cheque';

but simply changing the name there did not work. How can I change the name Woocommerce is using internally for this payment method?

Answer

So what you can do instead is to copy the source code from WC_Gateway_Cheque Class to a plugin file as explained below:

To make a custom gateway based on an existing WooCommerce payment method as cheque, It’s recommended to copy the source code from WC_Gateway_Cheque Class in a plugin (adapting the code for your needs).

You can copy the code to a php file that you will name for example wc-invoice-payments.php.

The code to copy:

<?php
/**
 * Plugin Name: WooCommerce Invoice Gateway
 * Plugin URI:
 * Description: Clones the "Cheque" gateway to create another custom payment method.
 * Author: Your name
 * Author URI: http://www.something.tld/
 * Version: 1.0.0
 * Text Domain: wc-invoice-gateway
 * Domain Path: /i18n/languages/
 *
 * Copyright: (c) 2016-2018
 *
 * License: GNU General Public License v3.0
 * License URI: http://www.gnu.org/licenses/gpl-3.0.html
 *
 * @package   wc-invoice-gateway
 * @author    Your name
 * @category  Admin
 * @copyright Copyright (c) 2020
 * @license   http://www.gnu.org/licenses/gpl-3.0.html GNU General Public License v3.0
 *
 * This "Invoice" gateway forks the WooCommerce core "Cheque" payment gateway to create another custom payment method.
 */
defined( 'ABSPATH' ) or exit;
// Make sure WooCommerce is active
if ( ! in_array( 'woocommerce/woocommerce.php', apply_filters( 'active_plugins', get_option( 'active_plugins' ) ) ) ) {
    return;
}
/**
 * Add the gateway to WC Available Gateways
 *
 * @since 1.0.0
 * @param array $gateways all available WC gateways
 * @return array $gateways all WC gateways + Custom gateway
 */
function wc_invoice_add_to_gateways( $gateways ) {
    $gateways[] = 'WC_Invoice_Gateway';
    return $gateways;
}
add_filter( 'woocommerce_payment_gateways', 'wc_invoice_add_to_gateways' );
/**
 * Adds plugin page links
 *
 * @since 1.0.0
 * @param array $links all plugin links
 * @return array $links all plugin links + our custom links (i.e., "Settings")
 */
function wc_gateway_invoice_plugin_links( $links ) {
    $plugin_links = array(
        '<a href="' . admin_url( 'admin.php?page=wc-settings&tab=checkout&section=invoice' ) . '">' . __( 'Configure', 'wc-invoice-gateway' ) . '</a>'
    );
    return array_merge( $plugin_links, $links );
}
add_filter( 'plugin_action_links_' . plugin_basename( __FILE__ ), 'wc_gateway_invoice_plugin_links' );
/**
 * Invoice Payment Gateway
 *
 * Provides an Custom Payment Gateway; mainly for testing purposes.
 * We load it later to ensure WC is loaded first since we're extending it.
 *
 * @class       WC_Invoice_Gateway
 * @extends     WC_Payment_Gateway
 * @version     1.0.0
 */
add_action( 'plugins_loaded', 'wc_invoice_gateway_init', 11 );
function wc_invoice_gateway_init() {
    class WC_Invoice_Gateway extends WC_Payment_Gateway {
        /**
         * Constructor for the gateway.
         */
        public function __construct() {
            $this->id                 = 'invoice';
            $this->domain             = 'wc-invoice-gateway';
            $this->method_title       = _x( 'Invoice payments', 'Invoice payment method', $this->domain );
            $this->icon               = apply_filters( 'woocommerce_invoice_icon', '' );
            $this->has_fields         = false;
            $this->method_description = __( 'Take payments in person via Invoice. This offline gateway can also be useful to test purchases.', $this->domain );

            // Load the settings.
            $this->init_form_fields();
            $this->init_settings();

            // Define user set variables.
            $this->title        = $this->get_option( 'title' );
            $this->description  = $this->get_option( 'description' );
            $this->instructions = $this->get_option( 'instructions' );

            // Actions.
            add_action( 'woocommerce_update_options_payment_gateways_' . $this->id, array( $this, 'process_admin_options' ) );
            add_action( 'woocommerce_thankyou_invoice', array( $this, 'thankyou_page' ) );

            // Customer Emails.
            add_action( 'woocommerce_email_before_order_table', array( $this, 'email_instructions' ), 10, 3 );
        }
        /**
         * Initialize Gateway Settings Form Fields
         */
        public function init_form_fields() {
            $this->form_fields = array(
                'enabled'      => array(
                    'title'   => __( 'Enable/Disable', $this->domain ),
                    'type'    => 'checkbox',
                    'label'   => __( 'Enable Invoice payments', $this->domain ),
                    'default' => 'no',
                ),
                'title'        => array(
                    'title'       => __( 'Title', $this->domain ),
                    'type'        => 'text',
                    'description' => __( 'This controls the title which the user sees during checkout.', $this->domain ),
                    'default'     => _x( 'Invoice', 'Invoice payment method', $this->domain ),
                    'desc_tip'    => true,
                ),
                'description'  => array(
                    'title'       => __( 'Description', $this->domain ),
                    'type'        => 'textarea',
                    'description' => __( 'Payment method description that the customer will see on your checkout.', $this->domain ),
                    'default'     => __( 'Receive an invoice...', $this->domain ),
                    'desc_tip'    => true,
                ),
                'instructions' => array(
                    'title'       => __( 'Instructions', $this->domain ),
                    'type'        => 'textarea',
                    'description' => __( 'Instructions that will be added to the thank you page and emails.', $this->domain ),
                    'default'     => '',
                    'desc_tip'    => true,
                ),
            );
        }

        /**
         * Output for the order received page.
         */
        public function thankyou_page() {
            if ( $this->instructions ) {
                echo wp_kses_post( wpautop( wptexturize( $this->instructions ) ) );
            }
        }

        /**
         * Add content to the WC emails.
         *
         * @access public
         * @param WC_Order $order Order object.
         * @param bool     $sent_to_admin Sent to admin.
         * @param bool     $plain_text Email format: plain text or HTML.
         */
        public function email_instructions( $order, $sent_to_admin, $plain_text = false ) {
            if ( $this->instructions && ! $sent_to_admin && 'invoice' === $order->get_payment_method() && $order->has_status( 'on-hold' ) ) {
                echo wp_kses_post( wpautop( wptexturize( $this->instructions ) ) . PHP_EOL );
            }
        }

        /**
         * Process the payment and return the result.
         *
         * @param int $order_id Order ID.
         * @return array
         */
        public function process_payment( $order_id ) {

            $order = wc_get_order( $order_id );

            if ( $order->get_total() > 0 ) {
                // Mark as on-hold (we're awaiting the invoice).
                $order->update_status( apply_filters( 'woocommerce_invoice_process_payment_order_status', 'on-hold', $order ), _x( 'Awaiting Invoice payment', 'Invoice payment method', $this->domain ) );
            } else {
                $order->payment_complete();
            }

            // Remove cart.
            WC()->cart->empty_cart();

            // Return thankyou redirect.
            return array(
                'result'   => 'success',
                'redirect' => $this->get_return_url( $order ),
            );
        }
    } // end WC_Invoice_Gateway class
}

Code goes in functions.php file of your active child theme (or active theme). Tested and works.

Then enable WooCommerce Invoice Gateway plugin in admin.
Now in WooCommerce settings, Payments section, you can enable this payment gateway.

You can unset / remove original Cheque payment gateway changing the 1st function like:

add_filter( 'woocommerce_payment_gateways', 'wc_invoice_add_to_gateways' );
function wc_invoice_add_to_gateways( $gateways ) {
    $gateways[] = 'WC_Invoice_Gateway';

    unset($gateways['WC_Gateway_Cheque']; // Remove Cheque gateway

    return $gateways;
}

It should work as expected.

Related: Extending WooCommerce COD payment gateway in a plugin

---

Initial answer:

As all payment gateways extend WC_Payment_Gateway Class, if you look to get_title() method you will see that you can use the filter hook woocommerce_gateway_title.

So for "cheque" payment Id, you will use it as follow:

add_filter( 'woocommerce_gateway_title', 'change_cheque_payment_gateway_title', 100, 2 );
function change_cheque_payment_gateway_title( $title, $payment_id ){
    if( $payment_id === 'cheque' ) {
        $title = __("Something else", "woocommerce");
    }
    return $title;
}

Code goes in functions.php file of your active child theme (or active theme). Tested and works.