I'm not even going to talk much about the fluff. It's exactly as I expected though, given the Thatcherite post-modernist GW mindset of the company; Their Dystopian Age is a crapsack world full of inherent human corruption made worse by Sturginium's powers, while Spartan's Sturginium Age was a positive world climbing to toward Utopia falling into the temptation of Sturginium rather than its promise.
I think for me the fluff has some big problems that emerge from coming awkwardly shoving DWars into the WWX setting
1. The idea of what conflict means I've discussed above with Zac, but at a basic level you don't carry out a secret skirmish war between competing powerful men and women with with toy battleships. Battleships, and battle fleets are major investments and require the infrastructure of a state. Even Spartan's mercenary companies were pushing it until they fleshed out the Italian and covenant fluff. They aren't something that carry out covert ops.
2. The dark cynicism of plots and machinations again doesn't fit a wargame like this. You can talk about unrest at court but I would want to hear more about the naval structures and areas of conflict, not that prince Zog is full of alien brain slugs and Princess Elsa's ice powers are part of a conspiracy by the omniscient council of vagueness.
3. The approach to non-western powers is really unpleasant, just the worst. I get it with gang leaders in the old West, but treating foreign princes as either magical demi-gods powered by nonsensium or senile idiots being manipulated is orientalist nonsense and dehumanising, and even worse doesn't fit the nations they are discussing. The whole Celestian empire and Latin alliance concrete landmass blocs of nations removes the potential for conflict between traditionally belligerent nations and removes agency from historically independent peoples, and is just lazy.
4. Spend some time telling me about how the fleets and commanders operate. Mention some commanders.
5. Why isn't there a war? The Japanese blew up Singapore! You can't just hide that under a rug.