How to push a character backward using root motion animations

I´m working on some sort of a fighting/brawler game. We are using root motion based animations for the attacks, but characters don´t push each other, so when a character attacks the other one, while being close together, is like doing soagainst a static wall/collider. The recieber is not pushed back by the attacks.

We´ve tried different things, but none of them seem to work.

Is there a standard aproach we are missing or something? or we can only sync every hit animation with every attack animation?