To model the Battle of the Somme with even some tactical fidelity is also likely not feasible within present constraints. I would look to niche war sim board games instead.
That said, one might be wiser to read the English war poets than search for such a game. The study of Great War tactics is perforce the study of a macabre failure in human imagination and morality. Even at the tactical level the war is proof of a human inability to learn and change - even when our choices lead inexorably to mass death.
Battlefield mortality was exacerbated by commanders’ fixation on 19th century tactics. Creeping artillery barrages and over-the-top frontal assaults were finally effective only strategically, as economic and political weapons. This was not tactical innovation. It was an upscaled iteration of cannon barrages decimating bravely advancing line infantry.