I thought it might be something like that. Since I have two different fields (same field names but different keys) I’ll have to use something like this, yes? https://github.com/Hube2/acf-filters-and-functions/blob/master/acf-reciprocal-relationship.php
But if the field is has the same key on both sides, I can use the the normal snipped (https://www.advancedcustomfields.com/resources/bidirectional-relationships/) but just change acf/update_value/name=related_posts to acf/update_value/key=field_cba9876543210 ?
