how can i add billing information in invoice email
I've implemented similar functionality for a Drupal Commerce site I built using Commerce Kickstart 2. It's actually a Rule created by the commerce_email module which I'll break down for you below:


Rule is called "Send an order notification e-mail (Customers)"
Event: Completing the checkout process
Action: Send mail with variable (contains all default commerce_email variable settings)


Then if you navigate to the Commerce Email admin section: (/admin/commerce/config/email)

The token I use to display the customer address is:

[commerce-order:commerce-customer-shipping:commerce_customer_address]

Using that token everything prints out in my email template correctly as expected.

Hope this helps!