Comment by Jjd0 on Kimetsu No Yaiba - Chapter 157: Returning Soul

It's because Shinobu has spent all her time making poison, antidote, also medicine and making other research that's why her sword has no blade but only has a pointy top where all she has to do is stab her enemies with it bc poison is in it.  While Kanao train on her swords techniques, stamina and did other other training that's why she's stronger than Shinobu