Add a Custom Button to Admin Sales Order View

di.xml

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <type name="Magento\Sales\Block\Adminhtml\Order\View">
        <plugin name="sales_order_adminhtml_view_custom_button_plugin" type="MageVision\Blog27\Plugin\Sales\Block\Adminhtml\Order\View"/>
    </type>
</config>

View.php

<?php
namespace MageVision\Blog27\Plugin\Sales\Block\Adminhtml\Order;

use Magento\Sales\Block\Adminhtml\Order\View as OrderView;

class View
{
    public function beforeSetLayout(OrderView $subject)
    {
        $subject->addButton(
            'order_custom_button',
            [
                'label' => __('Custom Button'),
                'class' => __('custom-button'),
                'id' => 'order-view-custom-button',
                'onclick' => 'setLocation(\'' . $subject->getUrl('module/controller/action') . '\')'
            ]
        );
    }
}