Miguel Hidalgo is considered to be a hero of Mexico. Which of these is a major way in which he differed from Toussaint L'Ouverture and Simón Bolívar, who are national heroes of other countries?

Well, there are many reasons that these three men, Toussaint L'Ouverture, Simon Bolivar, and Miguel Hidalgo, were very important to the Latin American Independence Movement. Although, I will sum it up so you won't spend hours reading this:

Freeing Latin America has involed many people. It was a long and hard struggle. Though, many failed, many still ended up succeeding. Toussaint L'Overture tried to free Haiti from France (failed but Haiti did still end up getting their independence), Simon Bolivar tried to free multiple countries, such as Venezuela (succeeded plenty), and last but not least Miguel Hidalgo tried to give Mexico's independence for Spain (failed).