There is no definitive answer to what the best horse in RDR2 is, as it depends on personal preference and how the horse will be used. However, there are several horses that are considered to be among the best in the game based on their stats and abilities. Here are some of the top horses according to various sources:

• Rose Grey Bay Arabian: This horse is considered the best in the game by many sources, including IGN and Polygon. It has a rating of 7 in health and stamina, and 6 in speed and acceleration. It is also listed as "Superior" in the games ranking system.

• Missouri Fox Trotter: This horse is considered the fastest in the game and is the best horse in Red Dead Online according to Dexerto. It has a speed base of 7 and an acceleration base of 5.

• Turkoman: This horse is considered one of the best by some players on Reddit. It has good stats and is known for being brave and calm in combat.

• Dutch Warmblood: This horse is considered a workhorse in RDR2 and has a good balance of stamina, health, and speed. It is a solid choice for general travel and work needs.

• Hungarian Half-bred: This horse is an exceptional warhorse and is built sturdier than other breeds. It sacrifices speed and acceleration in favor of health and stamina.

Its worth noting that any horse can be a good choice with the right saddle and stirrups. Additionally, some horses may be better suited for certain tasks, such as racing or combat, while others may be better for general travel and exploration. Ultimately, the best horse in RDR2 is the one that suits the players needs and preferences.