Yeah, I'm inclined to think S2 and S3 are both 3 coin for Ryoshu. She throws out daggers 3 different times for s2, and for the s3, I'm guessing the stab is a coin, dragging it through them is a coin, and the flourish to pull it out and dash forward is a coin Especially because Ryoshu tends to be heavily damage spec'd in her IDs so a low coin s3 seems unlikely unless it hits really hard or has some nasty debuffs
for ryoshu skill two she seems to throw multiple volleys of daggers from what I counted three volleys so that would make it alongside the first hit four coins
