Valar Morghulis is a common greeting in Braavos, meaning “all men must die” in High Valyrian. It is meant in the sense of “all men must (eventually) die”, sooner or later, somewhat like the Latin saying “memento mori”. The customary response is Valar Dohaeris — “all men must serve”.
The actual translation is not mentioned in the episode of the same name nor in the show so far and was not provided until Walk of Punishment.
This is not some hate filled phrase. It’s just a common greeting. Lets not dramatize and put too much meaning in such a phrase. There is no message of sublimation or domination. It is a simple matter of life.