You cut out a portion at the beginning that may be relevant depending on how one defines Fascism (as academia never fully and completely agreed on the definition).

Duvos is an antagonistic force that collects destructive Old World weaponry in an effort to conquer the world,[1] though it has yet to be directly seen in the My Time series. Duvos is known for having smog, an unusual sight above most other civilizations since the end of the Age of Corruption[2].

However, I think the stronger argument against Duvos being Fascist is further down.

The economy of Duvos is significantly impacted by its agricultural challenges. During a conversation between Duvos Soldiers and Mort and Zeke, the soldiers from Duvos reveal that their homeland suffers from harsh weather and scarce sunlight, leading to low crop yields. This suggests that the Empire's aggressive militaristic stance may be driven, in part, by the need to secure resources, especially food. One soldier shares a personal note about his sister aspiring to be a botanist, aiming to address the nation's food scarcity. The conversation hints at a hope that if Duvos could resolve its agricultural issues, the need for conflict might diminish.

Duvos being domineering due to suffering from a food shortage seems more colonialist out of necessity than out of a fascist ideology. At the same time, without actually seeing the country's inner workings, it's hard to say.

Here's a way back link to the game's lore, as cited in the wiki.