Get author meta data with no published posts in author.php?

Instead of that try using;

<?php get_userdata( $userid ); ?> 

For example;

<?php 
  $user_info = get_userdata(1);    // get info for user id '1'
  $username = $user_info->user_login;
  $first_name = $user_info->first_name;
  $last_name = $user_info->last_name;
?>

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