No. I went ahead and searched. If you gain the extra slot in expert mode you can only access it in an expert or master mode world, if you take that character back into a. Fixed bug where info accessories displayed info when you looked at empty signs but not when you looked at texty signs. There are cheat tools / methods which allow a 7th slot but none. Most accessories must be placed in their accessory equip slots, seen at the bottom right of the image, for their effects to apply. . After I defeated the invasion, I was sorting my inventory and was surprised to see that I had 7 accesory slots. There is absolutely no way to unlock more than 6 accessory slots legitimately. Added vanity & dye slots for accessories.