Niniashvili also plays full-back for the Georgian National Team[1] He participated in the 2019 European Under-18 Rugby Union Championship organised in Kaliningrad.

Although only evolving in the regional league, being 18 years old and having no high-level experience, he was selected by Levan Maisashvili to participate in the Autumn Nations Cup.

He scored his first international try against Russia at 2021 Rugby Europe Championship In 2021, he signed a three-year contract with Lyon.

Niniashvili played a crucial role in Lyon's success, helping the team win the Challenge Cup, their first European title in history.

His impressive performances caught the attention of the rugby world, and he was included in the Barbarians squad to face England in June 2022, despite having only 11 test caps at the time.