This function allows you to overwrite the default Elegant Themes function for displaying the footer credits (use it in the functions.php of your child theme) and make it also render shortcodes.

functions_footer-credits.php

function et_get_footer_credits() {
	if ( et_get_option( 'disable_custom_footer_credits', false ) ) {
		return '';
	}
	$credits_format = '<%2$s id="footer-info">%1$s</%2$s>';
	$footer_credits = et_get_option( 'custom_footer_credits', '' );
	if ( '' === trim( $footer_credits ) ) {
		return et_get_safe_localization( sprintf( $credits_format, '&copy; [jahr] Sibylle Brechtel', 'p' ) );
	}
	return do_shortcode(et_get_safe_localization( sprintf( $credits_format, $footer_credits, 'div' ) ) );
}