Custom forms that use advanced templates are printed in the locale of the current user, set in the Language field at Home > Set Preferences. Based on the locale, the font family is set.
You also can print these forms in the locale of the customer associated with a transaction, for transaction types that support this option at Transactions > Management > Print Checks and Forms.
ISO standards are followed for the country and culture code for each language (ISO 639 and ISO 3166 respectively).
When printing a template, only one locale can be selected. However, it is possible to combine languages and alphabets within one template if all of the required fonts are linked to the template and the lang attribute is set correctly.
For reference please see the suite answer Id:66473