iirc, Maldraxxi, as users of necromantic power, can pretty much go back and forth between the realms of the living and the Shadowlands. This doesn’t seem to get huge focus though from what I’ve seen.
Then again, I’m not entirely caught up with 9.1, nor have I finished every Covenant story (I’ve only finished Revendreth’s), so I’m not exactly an expert on SL lore haha.