If you want to use your own version of "left" and "right" then you can put Nazis anywhere you like.
But for some reason a good portion of academia (to not say most) labeled right as authoritarian and violent, and left as humanitarian and progressive. Hell, even Wikipedia and Google definitions says that national socialism is a far right-wing movement. So I don't blame you, definitions are a bit messy
I actually think the 2D version discussed in your link makes a lot of sense overall. But I think it's a mistake to label the horizontal axis as "Left/Right." Just label it "Collectivist/Individualist" like the vertical is labeled "Authoritarian/Libertarian."