The Epic Critical Boon has been removed (at least for main play).
Retaliation is better since Reckless Attack works with it.
Two-weapon fighting is worse than UA5 since barbarian can no longer pick up a level 1 fighting style. It's back to the same as the PHB.
Flex has been removed as a weapon mastery option. The longsword/war pick/warhammer/spear/quarterstaff are now Sap/Sap/Push/Sap/Topple, respectively.
You can't use the Dual Wielding feat and have a d10 weapon in one hand using Flex anymore. Nor can you do something like battleaxe/shield and keep the d10 damage die.
Despite that, the damage potential for two-weapon or weapon/shield fighting is not that bad, though that's largely helped by the use of the new Frenzy (using my Berserker spreadsheet). You also have a fair number of weapon mastery options, including Sap on the versatile weapons that formerly had Flex, allowing you to partially compensate for Reckless Attack.
Primal Champion is restored to level 20, and returns to granting +4 Str and Con. However it has an odd interaction with standard ASIs now. Because of the change to ASI, where at level 19 your maximum increase on the stat is 22, technically you could raise your Str to 22 at level 19. Then at level 20 with Primal Champion you get another +4 — however, Primal Champion only raises your max to 24, which means you only get +2 Str (raised from 22 to 24). I'm not sure if this is intended.
Overall, there are still almost no uses for a barbarian's bonus action. The Eagle Wild Heart can Disengage+Dash, and the Zealot can use Zealous Presence, but that's all I can find offhand. This is probably good for the purpose of maintaining Rage, but it still feels like an empty spot for action options. On the other hand, it means dual-wielding and polearm mastery bonus attacks are not competing with anything else for that spot.