The answer is: The enslaved Africans received the most harsh treatment and were considered legal property
African Slaves would not receive any good treatment where ever they brought to. But many documents indicated that the treatment from the French can be considered to be harshers compared to other enslaving nations. For example, approximately around 20% of slaves that sent to French would die on journey from harsh treatment on ships alone. The French even established Code Noir, which specifically dictates the terms of conditions for the slaves as their masters' property.