Risen 2 used muskets pretty well in a fantasy action RPG sense, other flaws in the game aside. They felt powerful but slow, and you had to really time your shots right (and hit) or else you'd be swarmed and fucked. Greedfall recently also did rifles pretty well, as they hit armor from range before you ran in and hit the underlying health bar with swords. I see no reason muskets and the like can't work in a Skyrim setting, assuming they're used similarly to crossbows as jf8350143 says above. Powerful but very slow, easy to get swarmed, so they're balanced. If Obsidian handles attribute balance better than they did in Outer Worlds, you'd have to really sacrifice melee skill to specialize in muskets, limiting your combat abilities.