Each illustrations comes in 5 different artwork styles.
When you select the illustration, you'll be able to see 6 different "versions" of the illustration in the top menu.
It looks like this:
Just click in the one you prefer and the illustration will be updated automatically.
You can also change colors of the three versions on the left-hand side... try it!
Look a template using different versions:
This youtube video shows you how to do it https://www.youtube.com/watch?v=W3BJ-fpW5eE