Lee sung-kyung and our universe actress.. . These two actresses have similar facial expressions and acting styles…
I don't agree, I think they acting is completely different. It's true that the character of Lee Sung-Kyung also has a blank face in a lot of situation, but it's explained in the storyline that she shut herself emotionally because of her traumas. Despite of this, she still expresses a vide range of emotions in a very subtle way. Watching her acting I was really impressed how well she plays with her facial expressions and voice, it already gives so many layers to the seemingly plain character.
https://youtu.be/BWRSWXedZlM?si=V83zbrjaPanPeCNb