I'm not very knowledgeable on 40K, so I'll provide what I think will give Death an edge:
Based on their profile, the Eversor seems like a berserker hopped up on drugs, which doesn't sound like a very intelligent soldier, just going in and murdering insanely. Meanwhile, Death is a very clever fighter, good at exploiting his opponent's weaknesses.
Even if speed is equalized, Death is very skilled at dodging opponents who can keep up with him, even getting in a free counterattack when he dodges with perfect timing.
Death has defeated a large variety of enemies, most of them massive and powerful, as well as taken on the armies of Heaven, Hell, The Corrupted, and the Kingdom of the Dead by himself, while it seems like the Eversors are always part of a squad to take on similar forces.
Death's large variety of weapons, spells, and summons should at least close the gap between the Eversor's future tech.
In conclusion, I believe that with all these points, the fight could come down to a very high difficulty fight determined by whoevever can make the fatal blow first, but so far, I think Death will eventually win.