any time the appearance for the item “sunstrider sword” is used on my deathknight the transmog will not apply.
It can be selected and is in the ‘sword’ section.
I’ve noticed the same thing on my rogue. Can apply the transmog to main hand and it shows up, but swap to offhand and it reverts to default appearance.
The sword is flagged as main hand instead of one hand, meaning it cannot be off handed.