I came across another book which has close to the Messiah true name of Yasha

CHRISTS TRUE NAME IN THE  SEFER TOLEDOT YESHU

“Yeshu” is actually an acronym for the formula (ימח שמו וזכרו(נו (Y’mach Sh’mo V’Zichro(no)) meaning “may his name and memory be obliterated”.

Yasha is close to Yeshu, the saviours real name.  Yasha means Saviour in Hebrew, so the fact that the European Jews wrote down Yeshu for the Saviour is telling!

Sefer Toledot Yeshu (ספר תולדות ישו, The Book of the Generations/History/Life of the Messiah), often abbreviated as Toledot Yeshu, is an early Jewish text taken to be an alternative biography of Messiah. It exists in a number of different versions, none of which are considered either canonical or normative within rabbinic literature,[1] but which appear to have been widely circulated in Europe and the Middle East in the medieval period.[2][3] A 15th-century Yemenite work of the same was titled Maaseh Yeshu, or the “Episode of Messiah,” in which Messiah is described as being the son of Joseph, the son of Pandera (see: Episode of Messiah). The account portrays Messiah as an impostor.

The stories claim that Messiah (Yeshu) was an illegitimate child, and that he practiced magic and heresy, seduced women, and died a shameful death.[4] But they also show a paradoxical respect for Messiah.