Disappearing bodies/Thralls, hit registration

Game mode: [Online | Singleplayer]
Problem: [ Bug | Performance]
Region: [US]

Bodies disappear randomly; in a fight against multiple humanoid enemies, I will kill one enemy, turn to fight the next. After killing the second(or more) enemy, I will start to loot/harvest the bodies; at least one of the bodies will have simply disappeared. Additionally, after knocking out a thrall I will be dragging it back to my camp and it will occasionally just disappear; sometimes as soon as the bindings are attached, other times after dragging it across painstaking lengths. No indication of thrall waking up or anything, just gone.
Lastly, I have been noticing some areas with hit registration areas; most notably the Black Hand Galleon and some spots in Sinner’s Refuge, though I seem to stumble across these spots almost everywhere I go. In these instances, either my character and the enemy will be attacking each other with neither being damaged despite a lack of dodging or guarding, or my attacks will ghost through an enemy while they beat me to death. Much more rarely, I will be able to damage the enemy while their attacks ghost through my character.

Steps on how to reproduce issue: