"Justice Sensitivity" isn't a condition or a binary trait that you either have or you don't. It's a measurement in some psychological studies where they ask subjects to rate subjective injustices. The study that page links actually shows the ADHD kids having lower perpetrator justice sensitivity so it's not really that simple either, which I'll expand on below.

That Edge Foundation website isn't a good resource. It's SEO filler content for them to feed their coaching sales funnel.

The actual study it linked is more informative. They surveyed a group of kids about their reaction to different scenarios of injustice and also ADHD traits. They found a positive correlation between ADHD and sensitivity to injustice from the victim perspective, but substantially lower sensitivity to injustice from the perpetrator perspective.

Given that this study was purely in 10-19 year olds (mostly children) and the opposite results for victim and perpetrator injustice, I suspect it's just measuring emotional maturity among the kids. The study also noticed a high correlation with angry and anxious responses, which further supports the correlation to emotional and interpersonal maturity.