Woocommerce has wc-user-functions.php which checks to see if the email exists already. This plugin can work if the file is modified so that the check is removed. I’ve successfully did it and it works with the username generated by WooCommerce (although it should work without it being generated). There’s one line in wc-user-functions.php which is the culprit.
Instructions
1. You’ll first need to go to /wp-content/plugins/woocommerce/includes
2. Open file wc-user-functions.php in that directory
3. Change the following
FROM:
if ( email_exists( $email ) ) {
return new WP_Error( 'registration-error-email-exists', __( 'An account is already registered with your email address. Please login.', 'woocommerce' ) );
}
TO:
if ( email_exists( $email ) ) {
}
4. You’ll need to do this every time you update WooCommerce.
