Here is what I noticed about each member in this particularly video! Just some strengths and weaknesses I noticed in each in order of age (not a ranking)
Boa
I think it's very possible Boa just wasn't feeling well on this day. She seems to be purposefully holding back to save her energy, not even lip syncing or emoting for her own part in this practice, but you can still tell she has the technical skill to effortlessly pull of moves especially complicated footwork.
Taeyeon
I really noticed Taeyeon's efforts to enhance her hip movements and body rolls which adds a unique grace to the dance while still being cool kind of like a snake lol. She does struggle a bit with the faster moments but it's not very noticeable.
Hyoyeon
Hyo's style really works with the faster and more hip-hop elements of the dance. She's very good at working through transitions and maintaining the musicality of the performance even when she likely wasn't instructed to. Besides a few odd positioning moments, there's no consistent downside i saw lol.
Seulgi
She's really one of the most aware of every part of her body which has her being very accuracy of the moves, even the very small details, throughout. The only issue may be a lack of sharpness and power on moments that perhaps call for it. She usually maintains a more smooth style.
Wendy
Basically the opposite of Seulgi. She's giving in a lot of power, adding texture to the harder beats of the music and emphasizing choices in the movement of her head and shoulders especially. However, she is probably the least accurate in her body position, especially the lower body movement.
Karina
She's very aware of how to connect her moves and be on at every moment. She's also great at catching smaller details. Her timing is also very notable. I think her energy is sometimes a bit restricted in certain parts though. She goes for sharp and suddenly stopping moves which helps on the fast parts but sometimes loses the effect on parts where she could take her time more but only sometimes.
Winter
Winter is one of the cleanest dancers here, very good at the angles of her arm and legs bends. Basically always creating a good about of space to display optimally to the camera. I think she could focus more on the dynamics/textures she brings to the moves though. Softening softer parts and going harder on stronger ones particularly.