The tv series changes the focus. The best description I’ve seen is that the book is an ensemble piece with three equally important plot branches, Aziraphael and Crowley, the Them, and Shadwell, Newt and Anthema, that come together at the climax whereas the show is the Aziraphael and Crowley show. The role of the other characters is reduced and more about Aziraphael and Crowley explored. That also in general expands and explores Heaven and Hell and Angels and Demons in the GO verse.

I haven’t seen the show so I can’t speak for if that expansion makes the agender nature of Angels and Demon’s more explicit or if it is further explored in the show than in the book. Just that the scope to explore it is different.