pmpro-custom-email-data-variables-per-locale.php

<?php
/**
 * Set custom PMPro email data variables per locale.
 *
 * You can add this recipe to your site by creating a custom plugin
 * or using the Code Snippets plugin available for free in the WordPress repository.
 * Read this companion article for step-by-step directions on either method.
 * https://www.paidmembershipspro.com/create-a-plugin-for-pmpro-customizations/
 */
function my_pmpro_email_data_variables_per_locale( $data, $email ) {
	$user        = get_user_by( 'email', $email->email );
	$user_locale = get_user_locale( $user );

	if ( strpos( 'en_US', $user_locale ) === false ) {
		switch ( $locale ) {
			case 'fr_FR':
				$data['levels_url'] = 'https://example.com/fr/membership-account/membership-levels/';
				break;
			case 'de_DE':
				$data['levels_url'] = 'https://example.com/de/membership-account/membership-levels/';
				break;
		}
	}

	return $data;
}
add_filter( 'pmpro_email_data', 'my_pmpro_email_data_variables_per_locale', 10, 2 );