social/mail_template_multi_report/views/mail_template.xml

<?xml version="1.0" encoding="UTF-8"?>
<odoo>
    <data>
        <record id="email_template_form" model="ir.ui.view">
            <field name="name">email.template.form</field>
            <field name="model">mail.template</field>
            <field name="inherit_id" ref="mail.email_template_form"/>
            <field name="arch" type="xml">
                <field name="report_name" position="after">
                    <field name="report_line_ids">
                        <tree editable="bottom">
                            <field name="report_name"/>
                            <field name="report_template_id"/>
                            <field name="condition"/>
                        </tree>
                    </field>
                </field>
            </field>
        </record>
    </data>
</odoo>