account_invoice_views.xml

<?xml version="1.0"?>
<odoo>
    <!-- CUSTOMER INVOICES -->
    <record id="invoice_restrict_edit_form" model="ir.ui.view">
        <field name="name">invoice.form.inherit</field>
        <field name="model">account.invoice</field>
        <field name="inherit_id" ref="sale_ux.invoice_form"/>
        <field name="groups_id" eval="[(6, 0, [ref('group_restrict_edit_invoice')])]"/>
        <field name="priority">20</field>
        <field name="arch" type="xml">
            <field name="invoice_line_ids" position="attributes">
                <attribute name="attrs">{'readonly':[('type','=','out_invoice'),('sale_order_ids','!=',[])]}</attribute>
            </field>
            <xpath expr="//page[2]//field[@name='account_id']" position="attributes">
                <attribute name="attrs">{'readonly':[('type','=','out_invoice'),('sale_order_ids','!=',[])]}</attribute>
            </xpath>
            <xpath expr="//page[2]//field[@name='company_id']" position="attributes">
                <attribute name="attrs">{'readonly':[('type','=','out_invoice'),('sale_order_ids','!=',[])]}</attribute>
            </xpath>
            <field name="team_id" position="attributes">
                <attribute name="attrs">{'readonly':[('type','=','out_invoice'),('sale_order_ids','!=',[])]}</attribute>
            </field>
            <xpath expr="//page[@name='other_info']//field[contains(@name, 'origin')]" position="attributes">
                <attribute name="attrs">{'readonly':[('type','=','out_invoice'),('sale_order_ids','!=',[])]}</attribute>
            </xpath>
            <field name="date_invoice" position="attributes">
                <attribute name="attrs">{'readonly':[('type','=','out_invoice'),('sale_order_ids','!=',[])]}</attribute>
            </field>
            <field name="partner_id" position="attributes">
                <attribute name="attrs">{'readonly':[('type','=','out_invoice'),('sale_order_ids','!=',[])]}</attribute>
            </field>
            <field name="user_id" position="attributes">
                <attribute name="attrs">{'readonly':[('type','=','out_invoice'),('sale_order_ids','!=',[])]}</attribute>
            </field>
            <field name="fiscal_position_id" position="attributes">
                <attribute name="attrs">{'readonly':[('type','=','out_invoice'),('sale_order_ids','!=',[])]}</attribute>
            </field>
            <field name="date_due" position="attributes">
                <attribute name="attrs">{'readonly':[('type','=','out_invoice'),('sale_order_ids','!=',[])]}</attribute>
            </field>
            <field name="payment_term_id" position="attributes">
                <attribute name="attrs">{'readonly':[('type','=','out_invoice'),('sale_order_ids','!=',[])]}</attribute>
            </field>
            <field name="partner_bank_id" position="attributes">
                <attribute name="attrs">{'readonly':[('type','=','out_invoice'),('sale_order_ids','!=',[])]}</attribute>
            </field>
        </field>
    </record>

</odoo>