A little bit ago, I was exploring my first Barbarians, and noticed that a big, scary Greataxe was nearly always more effective than a Barbarian with two handaxes or even two battleaxes! So, I designed my own Primal Path that makes the rather flavorful dual-wielding Barbarian a good choice: The Path of the Axemaster!
When you take this path at 3rd level, you gain the Two-Weapon Fighting and Defense Fighting Styles.
I'm really hoping that this bit is balanced as many Barbarians won't be using any armor because of Unarmored Defense. This, of course, is where Two-Weapon Fighting seems a bit more appealing...
When you choose this path at 3rd level, while you dual-wield, you no longer need to focus on using the weapon in your other hand. When you take the Attack action and are holding a melee weapon in both hands, attacking with the off-hand weapon does not cost you your bonus action.
This one feature might be a tad unbalanced, as it solves the biggest problem for dual-wielders: you use your bonus action! The small chance that this is balanced is the fact that this feature focuses on improving two-weapon fighting rather than granting you different features.
At 6th level, you gain the Dual-Wielder feat.
Ah, simplicity. Normally I would argue against giving a feat as a feature, but this feat basically gets everything I wanted in this feature done anyways.
When you reach 10th level, you learn how to shield yourself with your axes. While raging and wielding two axes in your hands, you may choose to twirl the axes, forming a shield of sorts. During your rage, you have +2 to AC.
Roughly balanced by the level you get it at, I hope. Though, this essentially grants the Barbarian a shield...
Then again, many other classes can get bonuses on par with this through spells and features, too, so I'm fairly certain this is good.
At 14th level, you truly master your axes. You may also dual-wield Heavy and Two-Handed weapons. Additionally, you may knock a Large or smaller creature prone if your hit is critical or deals maximum damage.
The big oof. This really gives you everything a Dual-Wielding Barbarian needs to charge into battle like a boss and start smashing things for big damage. Dual-wielding Greataxes really goes against the rules, but hey, its a big strong Barbarian!
I hope this is balanced, but I am super-open to criticism! I would love to hear the community's thoughts before I playtest!