Hi,

To hide the margin field from the pivot view in the Sales Orders report using Odoo XML customization, you can override the view and make the field invisible using the following code:

<record id="sale_order_pivot_custom" model="ir.ui.view">

    <field name="name">sale.order.pivot.custom.inherit</field>

    <field name="model">sale.order</field>

    <field name="inherit_id" ref="sale.view_order_pivot"/>

    <field name="arch" type="xml">

        <xpath expr="//field[@name='margin']" position="attributes">

            <attribute name="invisible">1</attribute>

        </xpath>

    </field>

</record>

Hope it helps