A brief discussion of the main characters in "That Evening Sun" can be found in the Characters section of the enotes study guide to the story: http://www.enotes.com/evening-sun/6983
Ten characters are listed there.
If you count every person mentioned in the story, there are a few more. There's Mr. Lovelady, who is "a short, dirty man who collected the Negro insurance." The husbands of the laundry women are mentioned as a group.