Uploading Articles
The Upload Articles section allows you to upload multiple text files containing only a title and content for the article. After uploading the posts, the Extension then gives you the options to publish articles immediately as posts or pages, set the category, and allow/disallow comments.
Inserting Articles
Second, the more powerful method allows you to add multiple articles in one or more .txt or .csv files. That is not all. Using this method, you can set the article title and body and article slug, categories, tags, excerpt, author, etc.
After uploading articles, the Extension also allows you to edit the uploaded content before publishing. This way, you will be able to set any other post settings such as Yoast SEO.