What do we learn from "va'Haricho b'Yir'as Hashem"?
Sanhedrin 93b #1: This teaches that Hashem loaded Mashi'ach with Mitzvos and afflictions like a Reichayim (millstone).
Sanhedrin 93b #2: It teaches that he is Morach (smells, i.e. senses who is guilty) and judges - "v'Lo l'Mar'e Einav Yishpot... v'Shofat Tzedek." Bar Koziva ruled for two and a half years, and told Chachamim that he is Mashi'ach. They tested him, and saw that he cannot judge by 'smell', so they killed him.
Rashi: He will fill (inspire) him with a spirit of Yir'as Hashem.
Radak: Smell is a light sense. Therefore, anything with a light sense is called Rei'ach. Also from afar, one senses war, when the wick of Ne'ores smells fire. [Mashi'ach] will sense good people and evil. He will not need to see with eyes and hear with ears to judge people and rebuke them. He will understand deeds via a little contemplation.
Radak citing his father: "Va'Haricho" is his speech, the breath of his mouth. This is like "l'Ravchasi l'Shav'asi" (Eichah 3:56). I.e. his speech will always be with Yir'as Hashem.
Malbim: Via Yir'as Hashem, he will become spiritual, and his physical powers will be stripped. He will not use senses of physical powers at all; he will be totally spiritual.
What do we learn from "v'Lo l'Mar'e Einav Yishpot"?
Rashi, from Sanhedrin 93b: Refer to 11:3:1:2.
Malbim: Mishpat is Bein Adam l'Chavero, to save a victim from his oppressor. A judge judges based on what his eyes see, who is liable and who is vindicated. Sometimes he errs, and the verdict is unjust. Mashi'ach will not judge based on what his eyes see. Rather, he will know the truth via his spirituality.
Why does it say "v'Lo l'Mishma Aznav Yochi'ach"?
Malbim: Rebuke is for bad deeds that he finds out about them. Normally, one rebukes based on what he heard people tell - "Lo Tovah ha'Shemu'ah Asher Anochi Shome'a Ma'avirim Am Hashem" (Shmuel I, 2:24). Sometimes he hears the opposite of the Emes. Mashi'ach will rebuke based on knowing the matters via his Ru'ach ha'Kodesh.
