"White nationalists" aren't a group per se, similar to Antifa. White nationalists are a set of groups, some worse than others. Antifa is a set of groups, some worse than others.
I don't recall ever reading about white nationalists being responsible for the deaths of millions of people. Perhaps you are confusing white nationalists with socialists or communists? Can you provide links to where white nationalists are responsible for millions of deaths?
And yes, members of Antifa has killed people, recently even, but I didn't mention anyone killing anyone, I mentioned violence. Do you need me to send you links to Antifa violence?