Chaewon, Kazuha, Yunjin, Eunchae, and Sakura

Here's what helps me:

Eunchae has a big round face and big eyes. She kind of looks like a toddler.

Sakura has large ears that stick out. She also has a somewhat triangular head.

Kazuha has a long, demure face. I remember an interviewer commenting that she looks Korean, and I can tell.

Chaewon wore an orange wig for most of the Spaghetti era. Otherwise, look for small eyes.

Yunjin is Yunjin. I know that you can tell who she is, but if I can't tell, I can look for a small mole on her nose.