Change the order of fields on the on the Member Profile Edit page.

pmpro-customizations.php

<?php

/**
 * This recipe changes the order of fields on the on the Member Profile Edit page.
 *
 * 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 mypmpro_member_profile_edit_user_object_fields($fields) {
	$fields = array(
		'user_email'	=> __( 'Email', 'paid-memberships-pro' ),
		'display_name'	=> __( 'Display name publicly as', 'paid-memberships-pro' ),
		'last_name'		=> __( 'Last Name', 'paid-memberships-pro' ),
		'first_name'	=> __( 'First Name', 'paid-memberships-pro' ),
	);
	return $fields;
}
add_filter('pmpro_member_profile_edit_user_object_fields', 'mypmpro_member_profile_edit_user_object_fields');