I can confirm that this bug happens in vanilla. I was AFK at the time, died on an empty cliff just above Devil’s Squat in the Exiled Lands. Seemed like I was killed by a Jhebbal Sag Werehyena Ambusher or fall damage after being attacked by one. When I came back my character was at the respawn location and unable to use “Rest on Shoulder” Hammers emote. I admin spawned a short sword (Alligator Bite) and an axe (The Mallet) to test if it applies to all weapon emotes and emote functionality returned after spawning the weapons.