Hi,
1. There is no such documentation. Since this requires PHP skills, we suppose that you can directly read the code where you want to do your change to know what you can do.
For the order_status you can use such tag in the HTML version: {VAR:order.order_status}
For the order_data, you can use such code:
<?php echo hikashop_getDate($data->cart->order_date); ?>
2. You can edit the file "address_template" for your template frontend and backend via the menu Display>Views and it will allow you to change the display format of the addresses.