Half -Orc Barbarian build advice

Hi all,

I am running a half-orc barb on the berserker path. he is currently a level 4 and he recently acquired a sentient sword with the consciousness of a deity. The deity communicates directly with the my character offering advice. To my mind this presents an opportunity for my character to multiclass in to maybe Paladin or Cleric with this being as the deity worshiped.

My question is would a Barbarian multiclassing into either Paladin or Cleric work, would it offer any worthwhile benefits and would it change my alignment?

Thanks in advance

It wouldn't change your alignment unless the deity in question would demand it in the case of a cleric. This would be akin to repenting of things that god disagrees with.
As far as paladin, in 5e they aren't really tied to deities anymore. They are based on an oath you make. That could very well be an oath made to a deity but it is not necessary. Their power comes from the devotion and force of will that the oath holds, hence charisma basedness.

That said aside from the fighting style and divine smites in paladin neither of those really seem that synergistic to me. War cleric could give you some cool stuff but those classes are usually ones that one wants a lot of levels in to make a big impact.
My suggestion would be to ask your dm about the Hexblade Warlock option from this Unearthed Arcana. The flavor of making a pact with the weapon is spot on and 2-3 levels in warlock could add some great spice to your barbarian build. When you aren't raging or when you want some spell options your slots recharge fast enough to be burned and even when you are raging some of the evocations and features carry over.