my-pmpro-change-text-for-login-and-widget.php

<?php
/**
 * This recipe will change the "Username or Email Address" text string
 * on the login page and login widget.
 *
 * 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/
 */

// Apply text changes by adding our filter.
function my_pmpro_login_page_only_gettext() {
	// Add the filter that will change the text strings.
	add_filter( 'gettext', 'my_pmpro_login_change_text_strings', 10, 3 );
}
// Hook into wp for the login page context.
add_action( 'wp', 'my_pmpro_login_check' );
// Hook into widgets_init for the widget context.
add_action( 'widgets_init', 'my_pmpro_login_page_only_gettext' );

// Only add our text filter when on the login page.
function my_pmpro_login_check() {
	// Check if we're on the login page.
	if ( function_exists( 'pmpro_is_login_page' ) && pmpro_is_login_page() ) {
		my_pmpro_login_page_only_gettext();
	}
}

// Change the "Username or Email Address" text string on the login page and widget.
function my_pmpro_login_change_text_strings( $translated_text, $original_text, $domain ) {
	// Let's change the text strings.
	switch ( $original_text ) {
		case 'Username or Email Address':
			$translated_text = __( 'Email Address', 'paid-memberships-pro' );
			break;
		case 'Please enter your username or email address. You will receive a link to create a new password via email.':
			$translated_text = __( 'Please enter your email address. You will receive a link to create a new password via email', 'paid-memberships-pro' );
			break;
	}
	return $translated_text;
}