Hey there,

Currently, EasyBlog built-in comment system does not have such a feature for it.

If you really want to allow users to upload files via the comment on a blog, I would suggest you to use Komento extension https://stackideas.com/komento.

Komento extension is a comment system which can integrate with Easyblog's comment system.

You can try it on our demo site, http://komento.stackideas.com/.