As a native of the state of West Virginia, I know people who are directly related to both of these clans amd the feud got some brief mention in our state history class, however, no ever such feud was ever discussed. I don't believe myself entirely ignorant on Appalachian history, and took courses on it in college, and seem to have not encountered any other feud discussed.
There have been a number. It's been said that feuds in academia are often bitter because the prizes are so small, and when you read that the Tolliver-Martin feud (aka the Rowan County War ) in eastern KY was started because one man maligned another's dog as a "yellow cur" , it seems familiar. The Rowan County War killed 20 people and wounded 16, also. But, unlike the less-bloody Hatfield-McCoy feud, it didn't result in two state governors at odds and the US Supreme Court asked to adjudicate, so it did not get as much notoriety. Eastern KY seems to have had more family feuds than WV ( I will confess to a slight WV bias, with my family roots in Hampshire Co. WV)
There were also feuds started over real grievances. The Bruen Lands Feud happened because a massive parcel of over 200,000 acres in Putnam, Jackson, Roane and Kanawha counties was badly surveyed when it was granted in 1796. That, and badly-recorded deeds resulted in sales of overlapping parcels by land agents and speculators in the 1840's. Things were already tense when the Civil War sharply divided the loyalties of the region. But then a delayed action by the Bruen heirs to claim their property in 1877 really blew things up: decades after many settlers had been working their farms, marshals appeared on their properties demanding they leave.
There were also real grievances that didn't result in feuds- like when the newly-created town of Elkins suddenly also became the new county seat of Randolph County after a convenient fire started in the Beverly courthouse and there happened to be a crowd of handy Elkins men available to move the county records to Elkins for, um, safe keeping. And the Civil War also created divisions that grew violent: the Casto Hole ( a cave) in jackson Co. was a notorious meeting place for Union militia to meet in an area that had a lot of Confederate sympathizers. Just because there was a war happening didn't mean the fights didn't get personal.
John Ed Pearse's The Days of Darkness is a good source for the eastern KY feuds. I notice that the late great musician John Hartford wrote a short piece on the Lincoln County Feud for the online WV encyclopedia., which also has a few other pieces on WV feuds.