Title, this skill is an inconsistent mess that misses more often than it can hit because of simple movement. At best Quickness does help, but it's ridiculous to ask always having Quickness constantly.
Axe to the contrary is "weaker" but only slightly and still has a lower cooldown with unblockable factor, the CC is more useful than the weakened sword 4 that is extremely telegraphed even with Quickness and immobilize on is extremely ineffective as people are found evading in the middle of it even after the first hit which should not be possible, perhaps it's lag but in that regard makes the skill terrible also. Being that Axe is also somewhat easier to evade still is going to reliably hit more often than the current Deathstrike, which shouldn't be a thing.
Off-hand Sword honestly has lost a lot of it's usefulness and became more of a buggy mess like hammer after a few patches, restoring what it used to be prior to chill (slow is welcomed but not necessary.) would greatly help gathering it's image and relevance back.
Willing to help with anything Revenant related.