I know about the other games, but i only played Nier Automata. I'm planning to play it again, because the first time i didn't pay enough attention to the story. Even though i had more than a 100 hours playtime, my friend keeps saying i never played Nier 😅
Discussion
Go back and play Drakengard 1-3 to assert dominance over your friend :)
There's another game called Nier Replicant which they were probably thinking of
Playing in release order will always be correct. But if you want timeline order it looks like this:
Drakengard 3 --> Drakengard 1 (5 endings)
Drakengard 1 ending A --> Drakengard 2 (dead end)
Drakengard 1 Ending E --> Nier Replicant (remake ending E) --> Nier Automata Ending E --> Nier Reincarnation (finale)