[Theme Horse Support Team]

Hi downtownuk,

the above shorcodes falls under the plugins territory now. So we cannot use such shortcode inside the theme. you may use below code in your child theme. Hope this may help you.
$output = '<div class="copyright">'.__( 'Copyright &copy;', 'attitude' ).' '.attitude_the_year().' ' .attitude_site_link().' | ' . ' '.__( 'Theme by:', 'attitude' ).' '.attitude_themehorse_link().' | '.' '.__( 'Powered by:', 'attitude' ).' '.attitude_wp_link() .'</div><!-- .copyright -->';

Thank you!