I think the only way to do it would be to create a publication with at least one editor and one contributing writer. When the post is submitted to the publication, the editor can go in and make changes. If you want to do a test, I set you up as a writer on one of my publications. You should get a notification.
Start a new story and write a sentence or two. Then go to the bottom of the page where you find the clap button and the social media icons. On the far right, you will see three circles. Click on that button and a pull down menu should appear (don’t know how it looks on a phone app) with the option “add to publication.” When you submit to the publication, I get a notice. When I publish the story, it should give me the ability to add or change text. When you look at your story, you will still have the ability to edit or add to the text.