odoo16/addons/purchase/report/purchase_reports.xml

<?xml version="1.0" encoding="utf-8"?>
<odoo>
    <data>
        <record id="action_report_purchase_order" model="ir.actions.report">
            <field name="name">Purchase Order</field>
            <field name="model">purchase.order</field>
            <field name="report_type">qweb-pdf</field>
            <field name="report_name">purchase.report_purchaseorder</field>
            <field name="report_file">purchase.report_purchaseorder</field>
            <field name="print_report_name">
                (object.state in ('draft', 'sent') and 'Request for Quotation - %s' % (object.name) or
                'Purchase Order - %s' % (object.name))</field>
            <field name="binding_model_id" ref="model_purchase_order"/>
            <field name="binding_type">report</field>
        </record>

        <record id="report_purchase_quotation" model="ir.actions.report">
            <field name="name">Request for Quotation</field>
            <field name="model">purchase.order</field>
            <field name="report_type">qweb-pdf</field>
            <field name="report_name">purchase.report_purchasequotation</field>
            <field name="report_file">purchase.report_purchasequotation</field>
            <field name="print_report_name">'Request for Quotation - %s' % (object.name)</field>
            <field name="binding_model_id" ref="model_purchase_order"/>
            <field name="binding_type">report</field>
        </record>
    </data>
</odoo>