To fit my requirement, I created my own template because it is pre-printed dot matrix report. Here is my template.
<?xml version="1.0" encoding="utf-8"?>
<odoo>
<record id="paperformat_invoice_sales_dot_matrix" model="report.paperformat">
<field name="name">Sales Invoice Dot Matrix</field>
<field name="default" eval="False"/>
<field name="format">custom</field>
<field name="page_width">215</field>
<field name="page_height">280</field>
<field name="orientation">Portrait</field>
<field name="margin_top">73</field>
<field name="margin_bottom">23</field>
<field name="margin_left">5</field>
<field name="margin_right">10</field>
<field name="header_line" eval="False"/>
<field name="header_spacing">68</field>
<field name="dpi">90</field>
</record>
<template id="sales_invoice_dot_matrix_report">
<t t-call="web.html_container">
<t t-foreach="docs" t-as="o">
<div class="header">
<div class="row">
Header
</div>
</div>
<div class="article">
<div class="page">
<div class="row justify-content-end">
Report Body
</div>
</div>
</div>
<div class="footer" style="font-size:12px;">
Footer
</div>
</t>
</t>
</template>
<report
id="report_sales_invoice_dot_matrix"
model="account.invoice"
string="Sales Invoice Dot Matrix"
report_type="qweb-pdf"
name="name"
file="name"
print_report_name="(object._get_report_base_filename())"
groups="account.group_account_invoice"
paperformat="paperformat_invoice_sales_dot_matrix"
/>
</odoo>
Hope these tips will helps: https://old.reddit.com/r/learnodoo/