Posted below are a range of responses to your question, and also links. Jonathan Brown's answer is quite detailed, and seems fairly plausible. In short, the person 'Uzayr could be an amalgamation of two personalities in history. Secondly, the term 'son of God', used in one of the Books of Enoch, has a different meaning from how Christians used the term. It just meant someone pious. There does not appear to be an extensive tafsir of this ayah in Imami books, but I will update this if I find it, inshaAllah.
"Meir Lipnick: Did any Jews actually refer to Ezra as the Son of God, as the Qur'an claims?
Originally Answered: Did any Jews actually worship Ezra as the son of God, as the Koran claims?
If such a sect existed ever, it would be such an outlier that no memory of it exists amongst the Jewish people today. Suffice it to say that every religion has groups of heretics that spring up from time to time. I had never heard of this particular bit of heresy before. When I wrote this answer: Meir Lipnick's answer to Who was Uzair in Jewish literature? about a year ago, I had never heard of this controversy, and had not thought of any reason why this question would be asked. Having read some of the other answers and discussion on this question, it makes sense. Still, this seems to be a very odd controversy. The discussion that it was only some small sect of Jews living in Yemen in the 11th century CE is quite baffling given certain legends that Yemenite Jews felt snubbed by Erza and no Yemenite Jews would name their children after him despite being a prominent biblical figure. See the Wikipedia article on Yemenite Jews
(early history). As the article continues, this particular legend is probably apocryphal, but the fact that it exists seems very counter to the passage in the Quran and any accompanying commentary.
What makes this even more baffling is the nature of this bit of heresy. The whole "son of God" motif is very pagan in character. All legitimate Jewish הַשׁקָפָה (outlook) characterizes God as a single entity, one non-corporeal being. The idea of Him having a son is simply a contradiction in Jewish theology.
Now, this did happen one time in history that such a heresy came about. Christianity could be said to have evolved from a Jewish heresy involving a cult of personality surrounding a particular individual. But, this doesn't translate well to Ezra. There was no cult of personality around Ezra. The Book of Ezra in Jewish scriptures clearly discusses a human being and his pivotal involvement in some of the goings on around the time the Jewish people first returned to Israel after the Babylonian exile. No claim in this book ever mentions anything supernatural about Ezra. He is regarded very highly as one of the founding members of the Great Assembly, but he's not even called a prophet! The era of prophecy ended when the first temple was destroyed many decades before Ezra. But the Book of Ezra shares no similar characteristics as the Christian New Testament. The cult of personality behind Jesus is quite obvious in the New Testament."
"A history of the Jews of Arabia Book by Gordon Darnell Newby Page 61 :
We can deduce that the inhabitants of Hijaz during Muhammad's time knew portions, at least, of 3 Enoch in association with the Jews. The angels over which Metatron becomes chief are identified in the Enoch traditions as the sons of God, the Bene Elohim, the Watchers, the fallen ones as the causer of the flood. In 1 Enoch, and 4 Ezra, the term Son of God can be applied to the Messiah, but most often it is applied to the righteous men, of whom Jewish tradition holds there to be no more righteous than the ones God elected to translate to heaven alive. It is easy, then, to imagine that among the Jews of the Hijaz who were apparently involved in mystical speculations associated with the merkabah, Ezra, because of the traditions of his translation, because of his piety, and particularly because he was equated with Enoch as the Scribe of God, could be termed one of the Bene Elohim. And, of course, he would fit the description of religious leader (one of the ahbar of the Qur'an 9:31R) whom the Jews had exalted."
"George Sale Alkoran of Mohammed page 152 (1923):
This grievous charge against the Jews, the commentators endeavour to support by telling us, that it is meant of some ancient heterdox Jews, or else of some Jews of Medina; who said so for no other reason, than for that the law being utterly lost and forgotten during the Babylonish captivity, Ezra having been raised to life after he had been dead one hundred years, dictated the whole anew unto the scribes, out of his own memory; at which they greatly marvelled, and declared that he could not have done it, unless he were the son of God. Al-Beidawi adds, that the imputation must be true, because this verse was read to the Jews and they did not contradict it; which they were ready enough to do in other instances
Jewish life in late Antiquity was relatively centralized in Sura, Pumbedita and Tiberias, with most Jewish splinter groups being obliterated by then (the emergence of multiple Jewish denominations is a modern phenomenon, while Karaites emerged during the late Abbasid period). The idea that God could have a son has been universally considered antithetical to Jewish thought.
Talmudic sages in general in general saw Ezra as the greatest figure after Moses. The Quran may present a mockery of Rabbinical Judaism by accusing Jews of calling Ezra son of God and taking Rabbis as their lords. Indeed, throughout the Sahih Bukhari and Sahih Muslim, many condemnations of Rabbinical Jewish practices could be found."
Quranic tafsir depicts Ezra in a slightly different way. Some tafasir say he was a prophet, although he could have just been the equivalent of a 'sabiq' (in Islam 'someone of the foremost group of righteous people').
"Uzair is Arabic for Hebrew Ezra. This is the only verse in the Holy Qur’an where such a reference is made. Who is this alleged Jewish son of God? After the Babylonian conquest of Jerusalem at the hands of Nebuchadnessar, the Torah was lost. Since there was none who remembered the law when the Jews returned from captivity, God raised up Ezra from the dead a hundred years after his death. When the Jews saw him thus raised from the dead, they said he must be the son of God. This is the contested view of some scholars. This raising from the dead is confused with another incident which actually took place to someone else and which is narrated in the Holy Qur’an in 2:261. It involves Bal’am (Balam) ibn Ba’r, a learned Israelite, who passed by a dead town (some say Antioch or one of its suburbs) and wondered how God would bring it back to life. The Almighty caused him to die then raised him back to life to see for himself that He can do anything at all."