Monster Hunter: World has proven to be a very popular entry into the series, however mods for the game have so far fallen into something of a gray area, most mods are just cosmetic in nature, and Capcom haven't stated what the repercussions could be should you install mods that may be seen as giving you a tactical advantage.
This new mod, therefore, while being very impressive and no doubt incredibly useful, may be one many players are not comfortable enough to install. The mod allows players to see a damage breakdown and DPS for your current team, allowing you to track damage during a hunt, in addition to your average DPS. It's a useful tool for learning the game and helping you and your teammates improve your performance.
The mod, by author MuriEX, is available here, if you're intrested in trying this mod and are not afraid of any potential consequences, then it's definately a useful mod to try.