etc/adminhtml/di.xml
<?xml version="1.0"?>
<!--
/**
* Copyright © EAdesign by Eco Active S.R.L.,All rights reserved.
* See LICENSE for license details.
*/
-->
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
<type name="Magento\Variable\Model\Variable\Config">
<plugin name="change_variable_controller"
type="Eadesigndev\Pdfgenerator\Model\Plugin\Config"
sortOrder="10"
disabled="false"/>
</type>
<type name="Magento\Sales\Block\Adminhtml\Order\Invoice\View">
<plugin name="change_print_button_url"
type="Eadesigndev\Pdfgenerator\Model\Plugin\Printinvoice"
sortOrder="10"
disabled="false"/>
</type>
</config>