pos/pos_barcode_tare/views/pos_config_view.xml

<?xml version="1.0"?>

<odoo>
    <record model="ir.ui.view" id="view_pos_config_form">
        <field name="model">pos.config</field>
        <field name="inherit_id" ref="point_of_sale.view_pos_config_form" />
        <field name="arch" type="xml">
            <xpath expr="/form/sheet/group[@name='features']" position="inside">
                <separator string="Loose good options" colspan="4"/>
                <group>
                    <field name="iface_tare_label" />
                </group>
            </xpath>
        </field>
    </record>
</odoo>