Would be a great crossover, especially in light of MHA's more recent chapters having the darker aspects and secrets of Hero Society exposed to the public and to the aspiring heroes of the main cast, which could potentially inspire a Champions-style revolt against the corruption of heroism among the younger heroes.
I remember that one. "Good is not a thing you are. Good is a thing you do." In retrospect, one could look at it as a warning against tautology, the tendency to presume that if someone is "good," that automatically imbues all their actions with that supposed goodness, regardless of how morally dubious or flat-out immoral those actions might actually be. In other words --- "You can't call yourself good and then use it as an excuse or justification to do bad things."
Very cute.