Well, to be honest I don’t think this questions is ‘valid’ anymore. I thought I had to change the code of the field group and put it somewhere manually to make my other question work (https://support.advancedcustomfields.com/forums/topic/required-field-based-on-input-other-fields/#post-84436). But since you helped me with that amazingly well I can just retrieve the original field keys from the php export and add the filter you mentioned in the other question to my functions.php file. I tested it and it works. Now only need to add the other validation rules. Thanks a lot. I will mark this question as answered
