Well it is directly compatible with Hexxit Beta so far at least, like I am able to just plug it in and it works fine, I havent done any extensive testing to see how it might interact with other mods, such as the zelda sword skills mod, the dual wielding could throw that off, or the more specialized and unique weapons/items may not work well if at all with the dual wielding, like hookshots, but my favorite feature by far is the shield+other weapon dual wielding, plus it has some other weapons with nice unique things about them, I would reccomend trying it out yourself, the mod page is here.
Another one I was thinking about suggesting and I was about to try out was one of the ship mods, such as Archimedes ships, or the Beta ship mod (choosing one is pretty difficult as they both have some major pluses and downfalls.)