gistfile1.txt

add_filter('agp_current_settings', 'agp_current_settings',1,1);

function agp_current_settings($options){
	if (is_product()){
		global $post;
		
		$product = wc_get_product( $post->ID );
		$id = $product->get_id();
		$postMeta = get_post_meta($id, 'Verkauf_ab', true);
		
		if($postMeta = '18'){
			$options['min_age']=18;
		}elseif($postMeta = '16'){
			$options['min_age']=16;
		}
	}
	return $options;
}

add_filter('agp_verify_age','agp_verify_age',1,2);

function agp_verify_age($show, $post_id){
	if (is_product()){
		global $post;
		
		$product = wc_get_product( $post->ID );
 		$id = $product->get_id();
		$postMeta = get_post_meta($id, 'Verkauf_ab', true);		
		
		if($postMeta == '18'){
			$show=true;
		}elseif($postMeta=='16'){
			$show=true;
		}
		if($postMeta== 'none'){
			$show=false;
		}
		return $show;
	}
}