At this time, MainWP doesn’t support direct inspection or management of files like wp-config.php or .htaccess across child sites for comparing or checking changes.
The File Uploader extension can upload files to child sites, but it does not facilitate bulk editing or inspections of files.
​Please feel free to make a suggestion about this on our feedback site. That way, others can vote for it, letting us know which features our users want the most. https://feedback.mainwp.com