MakeAPaymentMethodOnlyVisibleInAdmin

CheckmoPlugin

<?php

namespace MageVision\Blog77\Plugin\OfflinePayments\Model;

use Magento\Backend\Model\Auth\Session;
use Magento\OfflinePayments\Model\Checkmo;
use Magento\Quote\Api\Data\CartInterface;

class CheckmoPlugin
{
    private Session $backendSession;

    /**
     * @param Session $backendSession
     */
    public function __construct(
        Session $backendSession
    ) {
        $this->backendSession = $backendSession;
    }

    /**
     * @param Checkmo $subject
     * @param $result
     * @param CartInterface|null $quote
     * @return false|mixed
     */
    public function afterIsAvailable(
        Checkmo $subject,
        $result,
        CartInterface $quote = null
    ) {
        if ($this->backendSession->isLoggedIn()) {
            return $result;
        }

        return false;
    }
}