Does Zesty support adding/editing a .htaccess file?
Zesty.io does not use or support .htaccess files. This has to do with the technology powering sites as well as security decisions to protect websites.
However, you can accomplish most of the same functionality with other tools in Zesty.io such as the redirect creator. The information for that can be found here: https://developer.zesty.io/docs/seo-tools/redirects/