If you use a Survey Essay question, Storyline will send the response to the LMS if you include a Survey Results slide. Or, as I understand it, the response will also be sent if there's a Graded Results slide, as long as you include the Survey question(s) in the QUIZ SETTINGS of that Results slide.
How you retrieve the response(s) depends on the LMS. So talk to your LMS folks.
An essay question uses a text-entry field. When a text-entry field is inserted, Storyline automatically creates a text variable to store what is entered. That's known as the variable's value.
You can show any variable's value in a text box (or in the text within a shape) by typing the percent sign, the variable name, and another percent sign (for example: %textEntry%). Or you can add it via the Reference button on the Insert ribbon.
A variable's value is maintained throughout the course, so you can insert a reference on any slide. However, you can't show the value of a variable from another course. (Well, at least, you can't with just Storyline functionality.)