Create WordPress user though FTP.

create-user.php

<?php
/**
 * Create new user.
 *
 * @todo remove `prefix_` with your own slug.
 * 
 * @since 1.0.0
 */
if( ! function_exists( 'prefix_add_new_user' ) ) :
	function prefix_add_new_user() {

		$user_info = array(
	        'user_login'  =>  'admin',
	        'user_url'    =>  'http://example.com',
	        'user_pass'   =>  'admin@123',
	        'role'        =>  'administrator'
	    );

	    $user_id = wp_insert_user( $user_info ) ;
	}
	add_action( 'init', 'prefix_add_new_user' );
endif;