odoo16/addons/sale_expense/views/hr_expense_sheet_views.xml

<?xml version="1.0" encoding="utf-8"?>
<odoo>

    <record id="hr_expense_sheet_view_form" model="ir.ui.view">
        <field name="name">hr.expense.sheet.view.form.inherit.sale.expense</field>
        <field name="model">hr.expense.sheet</field>
        <field name="inherit_id" ref="hr_expense.view_hr_expense_sheet_form"/>
        <field name="arch" type="xml">
            <button name="action_get_expense_view" position="after">
                <button name="action_open_sale_orders"
                    class="oe_stat_button"
                    icon="fa-money"
                    type="object"
                    attrs="{'invisible': [('sale_order_count', '=', 0)]}">
                    <field name="sale_order_count" widget="statinfo" string="Sales Orders"/>
                </button>
            </button>
        </field>
    </record>
</odoo>