head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is variance, and it is a single point.

Optimization · Pure Optimization
A landmark strategy game combining a turn-based campaign for control of Rome with massive real-time battles.

Optimization · Pure Optimization
A strategy wargame pairing turn-based management of feudal Japan with real-time mass battles.
Rome: Total War leans Optimization (Pure Optimization); Shogun: Total War leans Optimization (Pure Optimization).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Rome: Total War
Real-time battle micro rewards quick unit handling
Shogun: Total War
Real-time battle micro matters but pace is forgiving
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Rome: Total War
Optional multiplayer battles; campaign AI is mappable
Shogun: Total War
Campaign AI daimyos follow mappable behaviors
Shogun: Total War leans a little harder on variance, though the gap is small.
Rome: Total War
Diplomacy and AI moves add modest fog
Shogun: Total War
Fog of war and agent rolls hide information
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Rome: Total War
Campaign economy, recruitment, and battle tactics are solvable
Shogun: Total War
Campaign economy, army composition and terrain are deeply solvable
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.