Custom Taxonomy Translation Base URL Filter

Some taxonomies add a custom rewrite rule to their newly registered taxonomies. In order to add the correct translated rewrite base you need to use the following filter:

add_filter( 'wordpress_multilingual_multisite_taxonomy_base', 'we_change_faq_topic_taxonomy_base', 20, 3 );
function we_change_faq_topic_taxonomy_base( $base, $taxonomy, $blog_id ) {

	if($taxonomy !== "faq_topics" && $taxonomy !== "faq") {
		return $base;
	}

	// Category / Term 
	if($taxonomy == "faq_topics") {
		if($blog_id == 11) {
			$base = 'wissensdatenbank/topics/';
		} elseif($blog_id == 8) {
			$base = 'knowledge-base/topics/';
		}
	// Post Type
	} elseif($taxonomy == "faq") {
		if($blog_id == 11) {
			$base = 'wissensdatenbank/faq/';
		} elseif($blog_id == 8) {
			$base = 'knowledge-base/faq/';
		}
	}

	return $base;

}