oca-financial/odoo-bringout-oca-account-invoicing-account_billing/account_billing/views/account_move_views.xml

<odoo>
    <record id="view_move_form" model="ir.ui.view">
        <field name="name">account.move.form.inherit.view.billing</field>
        <field name="model">account.move</field>
        <field name="inherit_id" ref="account.view_move_form" />
        <field name="arch" type="xml">
            <xpath expr="/form/sheet/group/group[1]" position="inside">
                <field
                    name="billing_ids"
                    widget="many2many_tags"
                    attrs="{'invisible': [('billing_ids', '=', [])]}"
                />
            </xpath>
        </field>
    </record>
</odoo>