2scents- looks like the second part of your question was answered by Menachem
As far as knowing who is tzadik etc- what we can measure is speech and action/ sometimes thought in facial expression etc
But beinoni and tzadik alike have mastered that. So that’s why I said you can see a tzadik is a different plane- like the Rambam says when he discusses nevuah- that after a Chacham reaches a certain level in Avodas Hashem- his senses become elevated- ie he gets ruach hakodesh and people can tell
Also I noted that when people struggle with evil, even if they do good, they will express that in their words as well… I hope that’s clearer