All the Jews were bilingual then because commerce and government went down in Greek. They needed Aramaic because that was the language of the Jews living in Mesopotamia and there was a lot of interchange. But most people didn’t know it.
Yeshu is a three-letter word just like cat. Yod, shin, vav. Once anyone learns a three-letter word, they never screw it up. That’s the only name the god in the new Greek myth was known by throughout Jewish history.
Yet it is present far before that idov - Joshua (Yeshu) long before the greeks.