Add "PIN Terminal" (Point-of-sale) as payment method

[Fidelity88]

Mollie has added a Point-of-sale payment method using a physical PIN terminal device (PIN = Dutch translation for POS). Meaning an in-person payment method as they describe it. Developer documentation can be found here.

We use this payment method on a custom built POS platform. When a sale is made, we push the order to WooCommerce using their REST API to create a new WooCommerce order.

In the POST request, the following data is sent to WooCommerce to mark the order as paid using Mollie:

        // Add Mollie META keys for payment transaction
        $meta[] = array(
            'key' => '_mollie_payment_id',
            'value' => $order['transaction_id'] // For example: "tr_ym4a59aTEU" according to attached screenshot
        );
        $meta[] = array(
            'key' => '_mollie_payment_mode',
            'value' => $mollieMode // For example: 'live' or 'test'
        );

        // Overrride payment method and payment method title
        $paymentmethods['payment_method'] = 'mollie_wc_gateway_ideal';
        $paymentmethods['payment_method_title'] = 'PIN';

Screenshot for the current situation with above POST request:

This method works, and even the "refund" button in WooCommerce works. But because of the chosen payment method, the title in the WooCommerce backend is shown as "Payment via iDeal". Where it would be better to show "Payment via PIN" or "Payment via POS"

The available list of accepted payment methods in the Mollie for WooCommerce plugin is:

'mollie_wc_gateway_bancontact',
'mollie_wc_gateway_belfius',
'mollie_wc_gateway_directdebit',
'mollie_wc_gateway_eps',
'mollie_wc_gateway_giropay',
'mollie_wc_gateway_ideal',
'mollie_wc_gateway_kbc',
'mollie_wc_gateway_sofort'

Would be great if, for example, mollie_wc_gateway_pos can be added to show "Payment via POS" on the WooCommerce backend instead of the current available options.