A map is planned, but it's going to be an unlockable by doing an item hunt quest. I'm kind of going for that vibe that DS1 has with figuring out the layout as you go, and having those 'Oh, this area connects to this area' moments.
Personally, I think that would make the game less enjoyable to play, just because I often have a hard time getting lost without a map in metroidvania type games, and dying in a place I don't remember how to get back to is very frustrating. I get the point of hiding the whole layout from the player, but locking the whole feature behind an objective sounds frustrating.