So your ‘old’ class is from 2020. Long after the Samurai was added and so the first version of this mechanic was in the game, though on testing.
I know what was being tested in 2018 was very different from the now. That though is just normal iteration. It seems likely they’ve been working on this for a while, as a Samurai variant, as the other features of the class, katana and heavy armour (not robe as many people assumed) are the same.
The dash mechanic also exists in other games, and in ROTMG as an enemy behaviour – the Jade and Garnet statues e.g. or the Murderous Megamoth. So no, your idea is neither original nor new.