On raw ability without training in chess, Caesar had better potential to win at chess than Napoleon. Caesar was a brilliant military engineer and strategist; possibly the best in the history of war. A sharp engineer might calculate chess board combinations better than a non-commissioned artillery officer . If one was drafting talent to play in the pro chess league Caesar would be selected in the first round while Napoleon would be lucky to be signed as a free agent.
Napoleon avoided facing the Russian General Suvorov- a wise choice for he would have lost in conflict, and made an expedition to Egypt instead. Caesar probably would have discovered a way to trap Suvorov instead of avoiding him until General Suvorov became hors de combat due to old age, as did Napoleon.