Hi,

Order payment result is stored in database in table COM_Order in column OrderPaymentResult.

You can use custom macro for this purpose in your e-mail template:

http://devnet.kentico.com/docs/devguide/appendix_a___macro_expressions.htm

In code of your custom macro you can access the data which you are looking for (OrderPaymentResult) format it according your needs and return.

Or, you can use following context macro, but this macro will not be resolved according your needs in the format you are looking for.

{%order.orderpaymentresult%}

Best regards,
Miroslav Remias.