Add Custom Link to Sales Order View Admin Panel

How can I add a custom link to ‘sales/order/view/order_id/123456’ adding an slash after the order_id with route name “download” so it becomes
sales/order/view/order_id/6710/download

My current route.xml file is

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:App/etc/routes.xsd">
    <router id="admin">
        <route id="order_export" frontName="order_export">
            <module name="Vendor_OrderExport" before="Magento_Adminhtml" />
        </route>        
    </router>
</config>

It’s redirecting to a new permalink showing as https://example.com/adminPanel/order_export/index/index/key/29847124871248214hjhsfh2bdhjsf21/