It is good to know that in ERPNext, custom print formats do not automatically display the header and footer. You can set the header as follows:
{% if letter_head and not no_letterhead -%}
{% if print_settings.repeat_header_footer %}
<br> <div class="letter-head">{{ letter_head }}</div>
{%- endif %}{%- endif %}You should follow a similar approach for the footer.
However, one thing to keep in mind is that the system offers translations only for the built-in (Standard) print formats. If you create a custom print format (based on an existing one), the labels must be entered in English as follows:
{{ _("Field Label Text in English") }}Later, you can use the ERPNext built-in translation tool to translate the labels into your desired language.