There is a work known as Tsavaat Rabbi Eliezer HaGadol, which is purported to be have been authored by the Tanna R. Eliezer. According to R. Menahem Lunzano cited here, the work was actually authored by the 11th century Ashkenazi R. Eliezer ben Yitshak.
Personally, given for example the numerous statements that seem to be based on the Zohar which was not published until the end of the 13th century, I wondered if it was of even later authorship. I see that this is the opinion of Gershom Scholem and Yeshaya Tishbi, cited here.
What does later research indicate regarding the provenance of this work?
For example, when did Scholem think it was written, if not in the 11th century.