Tzitzak (Irene) (-750)

"This individual is sometimes confused with Byzantine Empress Irene, who was her daughter-in-law.

Tzitzak (Greek: Τζιτζάκ) (died c. 750), baptised Irene (Greek: Εἰρήνη), was a Khazar princess, the daughter of khagan Bihar, who became empress by marriage to Eastern Roman Emperor Constantine V (r. 741–775)." - (Wikipedia (en) 11.08.2021)