Derech Eretz Zuta (1:5) says that Eliezer, the servant of Avraham, was one of the people to have entered Gan Eden alive, while in Pirkei D'Rabbi Eliezer (16:14) we are told Eliezer is the same person as Og, the king of Bashan, who was a rasha. What is the consensus by most meforshim? Was he a tzaddik, worthy enough to enter Gan Eden alive, a privilege only granted to a few select tzaddikim, or was he a rasha?
In this medrash Talpiot written by Hamekubal Rav Eliyahu Hacohen of Izmir about 300 years ago he writes in entry "Eliezer" (the entries are written in alphabetical order) Eliezer did a kabalistic concept called "Pirud" which basically means separating the bad side of ones neshama into another body. The bad side became Og Melech Haboshon and the good side became Blessed (as Lavan said "בא ברוך ה') and he entered into Gan eiden alive.
He also brings the Zohar that says about Ester that she also did Pirud and the bad side of her neshama which was removed into another body had relations with Achashveirosh and had a son Darius which might explain why all the kings of Persia henceforth were not recorded as adherents of Judaism.
I don't know the rabbinic "consensus", but I can add a useful source to the discussion.
Chida in Shem Hagedolim (Maareches Hagedolim, Mar Rav Avraham Gaon) notes that Mabit (1:276) states that people who name after Eliezer must be naming after Eliezer the son of Moshe Rabbeinu, because Eliezer was cursed (with the assumption by Chida based on this being that he was a Rasha). However, Chida himself concludes that he was a Tzaddik and Chacham (even asking on the Mabit based on this conclusion). He bases his opinion on Yoma 21b (in comments) and the source quoted above that he entered Gan Eden alive.
My edition of Pirkei d’Rebbi Eliezer contains a commentary called “Tov Ayin” (not sure who authored it) who asks a similar question:
רבים ראו כן תמהו על הפליאה הנשגבה הזאת שקורא לאליעזר רשע ואומר כי הוא עוג מלך הבשן. ובגמרא הלא אמרו שאליעזר עומד ומשמש אצל האבות הקדושים (ב״ב נח.), ואיך יתקיימו שני המאמרים האלה.
Many saw and were confounded by this awesome wonder that he calls Eliezer wicked and says that he is Og the king of the Bashan, but in the Gemara, do they not say that Eliezer stood and served the holy fathers? How can these two statements be reconciled?
This is fundamentally the same question as yours, just asked by contrasting the Midrash with a different statement of Chazal’s.
After stating that many have offered their own approaches and that he is wholly unqualified to offer his own, he gives a very simple answer to this question:
אין זה עוג שהיה בימי משה, רק בנו או נכדו, ומכל מקום קראו לאליעזר גם כן עוג עיון שהיה מלך הבשן. ומה שאמר שנתן לו הקב״ה שכרו בעולם הזה כדי שלא יהא שכר לרשעים בעולם הבא הוא כדי שלא יהיה לבניו שכר, ולכן לא אמר הלשון כדי שלא יהא שכר לרשע בעולם הבא, רק לרשעים, כי אליעזר בעצמו לא היה רשע, רק בניו אחריו, ולכן אמר לרשעים.
This is not the Og in the days of Moshe, but rather [that was Eliezer’s] son or grandson. Nevertheless he calls Eliezer also Og because he was the king of the Bashan. That which he says that Hashem gave him reward in this world so that there would not be reward for the wicked in the next world is so that there would not be for his children reward, and therefore it doesn’t say the wording “so that there would not be reward for the wicked [singular] in the next world,” only “for the wicked [plural],” since Eliezer himself was not wicked, only his children after him, and therefore he says “for the wicked [plural].”
He goes on to explain how this fits in with Moshe’s concern about Og’s merits: not his own personal merits, but those of his grandfather. He says that the one who came to tell Avraham that Lot was kidnapped was the previous king of Bashan, similarly called Og due to his position, and his throne was later occupied by Eliezer.
He proceeds to give a much lengthier second answer that has something to do with Klipos. If someone has a copy and understands the Kabbalah involved, feel free to write it up as a separate answer, but it’s way beyond me.