Huh, I feel like it's wrong on chapter 11 for him to say "I thought you'd use Simple Appraisal but you didn't", because she used "Appraisal" (he wouldn't know the difference), but just like she felt discomfort from being appraised, he too felt it from her appraisal.
This is also related to the fact that Simple Appraisal is usually a skill that is overwritten with more useful skills by adventurers, and since they have limited skill slots, having it indicates a newbie adventurer.
Kano indeed has already overwritten hers, and instead used a magic item to use the superior version of Simple Appraisal, but she can't show that to others, as it's a really rare item and could lead her into trouble.
Also, her speech at the end, it's "The true hero's power", she is talking about when her brother (Hero) defeated the Demon Lord (Wolgermut-kun). He had used Shadow Step