Traditionally, when you are fighting against a southpaw your goal is to land your right hand. You should be pushing your opponent’s right jab to your right while continuously stepping your left foot to the left (to the outside of their front right foot). It is obvious your opponent will be trying to do the same to you in order to land the left hand. This is an ongoing struggle.
Here Joana uses a different tactic. She leads with a left low kick while continuously moving to her left, the blind side of her southpaw opponent. This forces her opponent to reset and follow all the time. A subtle but nevertheless, very effective tactic.
A Machida-style throw is also available should you decide to mix things up and step in. I plan to post an example of such a throw next week.
My original post: https://www.bloodyelbow.com/2017/6/27/15876742/combat-course-lessons-from-the-cage-1-mma-grappling-striking-technique