I’m confused. In what way does sarcasm break paladin oaths? Not even devotion paladins would break their oaths via sarcasm. Here are the tenets of a devotion paladin:

Tenets of Devotion

Though the exact words and strictures of the Oath of Devotion vary, paladins of this oath share these tenets.

Honesty. Don't lie or cheat. Let your word be your promise.

Courage. Never fear to act, though caution is wise.

Compassion. Aid others, protect the weak, and punish those who threaten them. Show mercy to your foes, but temper it with wisdom.

Honor. Treat others with fairness, and let your honorable deeds be an example to them. Do as much good as possible while causing the least amount of harm.

Duty. Be responsible for your actions and their consequences, protect those entrusted to your care, and obey those who have just authority over you.

As you can see sarcasm isn’t mentioned.