Of course, nothing stops anyone from applying the DAZ displacement maps in Poser's Advanced Material Room by hand. I add displacement, bump, and now normal maps in the Material Room all the time.

There are also several applications (?Crazy Bump) that can convert good bump/displacement maps into normal maps. I have had some fairly good success doing this.

[Edited to add]

Also, Texture Converter 2 (a DAZ  product) does a fairly good job of converting bump/displacement maps between its supported figures.

LMK

Probably edited for spelling, grammer, punctuation, or typos.