Louise can't hold it still since the thug was so aggressive. She doesn't blame the elven woman that she can't made a clean shot, life is tough. Honestly, she is suck at team work which like with her and Erwin back then. 

She lured the thug and then casted Wind Chant to create a powerful wind burst, knock-backing the aggressive thug to give herself a rest for a bit. After the wind burst, the barrier has been created nullify both physical and magical attacks. It also could able to break another barrier by the wind burst when collide together before creating a wind barrier.