Mortal Engines story isn't accessible to GA and it won't fly high with book fans cause it's already sanitized. Book Hester is hideous and there's an actual plot point for it cause her split skull creates her mental instability and fits or murderous rage. It's incurable so she's a constant liability to the friendlies and that actually plays a big role in this installment and sequels. This chick is Kylo Ren/Jon Snow, a strategically placed scar meant to prettify, not to intimidate. fans are very peculiar about these things so they won't like it.
moreover, actors are just bland. They are Cara/DeHaan level. Cara was an action heroine too and the movie looked stunning, and absolutely nobody cared. And it isn't like the season is low on action heroines. SpiderGwen and Penny, Meera, Queen Nicole Kidman, Hailee Steinfeld do action in much more appealing movies.
I don't know why this was such a pet project of Jackson but yeah, there's no interest. IGN shills for anything anyway.