Let's say you were suddenly in Eorzea...

[Malzian]

Is the player character death permanent compared to npc player death like log horizon.

For terms of a gameplay mechanic, permadeath is not something one would associate with PCs. However, the fact that NPCs die and are unable to be revived means that the potential for it is there even if it's not something that would ever be applied as part of the game system to PCs. There's no way to know what would happen should you suddenly inhabit the body of your character, though, so sadly there's really only one way to find out.... (Though honestly my post was meant to be a bit of a lark, anyway.)