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

Optimization · Pure Optimization
Gunpowder-era Total War blending empire management with line battles.

Optimization · Pure Optimization
Optimising road networks and production chains at a settler's pace.
Empire: Total War leans Optimization (Pure Optimization); The Settlers II: 10th Anniversary 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.
Empire: Total War
Real-time battle micro is modest
The Settlers II: 10th Anniversary
Slow road-laying needs no dexterity at all
Empire: Total War leans a little harder on reads, though the gap is small.
Empire: Total War
Multiplayer line-battle feints exist
The Settlers II: 10th Anniversary
AI opponents expand on predictable scripts
Empire: Total War leans a little harder on variance, though the gap is small.
Empire: Total War
Campaign AI and battle dice noise
The Settlers II: 10th Anniversary
Map resources are scripted-but-unknown until explored
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Empire: Total War
Campaign economy and line-infantry tactics are mappable
The Settlers II: 10th Anniversary
Road networks and production chains are the entire game
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.