DisableCustomerWelcomeEmail

di.xml

<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <type name="Magento\Customer\Model\EmailNotification">
        <plugin name="magevision_disable_welcome_email" type="MageVision\Blog75\Plugin\Customer\Model\EmailNotificationPlugin"/>
    </type>
</config>

EmailNotificationPlugin.php

<?php

namespace MageVision\Blog75\Plugin\Customer\Model;

use Magento\Customer\Api\Data\CustomerInterface;
use Magento\Customer\Model\EmailNotification;

class EmailNotificationPlugin
{
    /**
     * @param EmailNotification $subject
     * @param \Closure $proceed
     * @param CustomerInterface $customer
     * @param string $type
     * @param string $backUrl
     * @param null $storeId
     * @param null $sendemailStoreId
     */
    public function aroundNewAccount(
        EmailNotification $subject,
        \Closure $proceed,
        CustomerInterface $customer,
        $type = EmailNotification::NEW_ACCOUNT_EMAIL_REGISTERED,
        $backUrl = '',
        $storeId = null,
        $sendemailStoreId = null
    ) {
        //Disable all welcome emails
        return;

        //Disable Welcome email, when confirmation is not enabled and customer set already a password (default)
        if ($type === EmailNotification::NEW_ACCOUNT_EMAIL_REGISTERED) {
            return;
        }
      
        //Disable Welcome email, when password setting is required
        if ($type === EmailNotification::NEW_ACCOUNT_EMAIL_REGISTERED_NO_PASSWORD) {
            return;
        }
      
        //Disable Welcome email, when confirmation is enabled
        if ($type === EmailNotification::NEW_ACCOUNT_EMAIL_CONFIRMATION) {
            return;
        }
      
        //Disable Confirmation email, when account is confirmed
        if ($type === EmailNotification::NEW_ACCOUNT_EMAIL_CONFIRMED) {
            return;
        }
    }
}