Replace as in “delete/overwrite the original”
Neither DLCs nor Sequels do that.
See the Witcher series
You have the individual parts (1,2 and 3) which are all related/build on one another, but are clearly separable from one another and are also very different technically. And then you still have the DLC for the individual parts, which expand the games but are too small to be a separate game.
Blood and Wine is an example of a DLC that could almost have been a standalone game.
The big difference to OW is that no sequel or DLC deletes the predecessor or base game and then replaces it.
I personally would call OW2 PvP a patch rather than a DLC.
In the end, it’s the same as in World of Tanks with 1.0, which switched to a completely new engine.
Some maps were removed, some of which came back later after an overhaul. But nothing has changed in the game per se except that it new graphics, new sound, new physics, new optical systems, etc.