James Tabor has a page
Ebionites & Nazarenes: Tracking the Original Followers of Jesus that touches on the link between the Ebionaens and the Essenes. Some excepts (my underlining):
It seems significant that the Dead Sea community also used this term Ebionite or “Poor Ones” to refer to their own movement (CD 19:9; 1QSb 5:21). This movement, that Josephus and others label as Essene (possibly from ‘Ossim, meaning “Doers of Torah”), who wrote or collected the Dead Sea Scrolls, pioneered certain aspects of this “Way” over 150 years before the birth of Jesus. They were a wilderness (out in the Arava, near the Dead Sea–based on Isaiah 40:3), baptizing (mikveh of repentance as entrance requirement into their fellowship), new covenant, messianic/apocalyptic group. They believed they were the final generation and would live to see the end and the coming of the Messiahs of Aaron and of Israel (the two anointed ones–priest and king)... They too referred to themselves as the Way, the Poor, the Saints, the New Covenanters, Children of Light, and so forth. Perhaps their most common designation was the Yachad–the brotherhood or community, and they referred to themselves as brother and sister. They were bitterly opposed to the corrupt Priests in Jerusalem, to the Herods, and even to the Pharisees whom they saw as compromising with that establishment to get power and influence from the Hellenistic/Roman powers. They had their own developed Halacha (interpretation of Torah), some aspects of which Jesus picks up (ideal of no divorce, not using oaths, etc.). They followed one they called the True Teacher (Teacher of Righteousness) whom most scholars believe lived in the 1st century BCE and was opposed and possibly killed by the Hasmonean King/Priests at the instigation of the Pharisees. John the Baptizer seems to arise out of this context and rekindle the apocalyptic fervor of the movement in the early decades of the first century CE...
The variety of self-designations used by the John/Jesus/James movement, many of which had previously been used by the Essenes, is telling. Indeed, one might call the Jesus movement a further developed messianic “Essenism,” modified through the powerful, prophetic influence of Jesus as Teacher and the leadership of James his brother for nearly 40 years.
Later, when Christianity developed in the 3rd and 4th centuries and gradually lost its Jewish roots and heritage, largely severing its homeland connections, the Gentile, Roman Catholic Church historians began to refer to Ebionites and Nazarenes as two separate groups—and indeed, by the late 2nd century there might have been a split between these mostly Jewish followers of Jesus. The distinction these writers make (and remember, they universally despise these people and call them “Judaizers”), is that the Ebionites reject Paul and the doctrine of the Virgin Birth or “divinity” of Jesus, use only the Hebrew Gospel of Matthew, and are thus more extreme in their Judaism. They describe the Nazarenes more positively as those who accept Paul (with caution) and believe in some aspect of the divinity of Jesus, even possibly the virgin birth, but viewed him as “adopted” as Son of God at his baptism. What we have to keep in mind in reading these accounts from the Church fathers is that they are strongly prejudiced against any form of what they call “Judaizing” among Christians and they share the view that “Christianity” has replaced Judaism entirely overthrowing the Torah for both Gentile and Jew.
I think it best today to use the collective term Ebionite/Nazarene in an attempt to capture the whole of this earliest movement, and it would be useful to revive the term Yachad as a collective designation for the community of the Hasidim/Saints. Ebionite/Nazarene is a good historical designation to refer to those original, 1st century, mostly Jewish, followers of Jesus, gathered around James the brother of Jesus in Jerusalem, who were zealous for the Torah, but saw themselves as part of the New Covenant Way inaugurated by their “True Teacher” Jesus. James is a key and neglected figure in this whole picture (see essays on James). As the blood brother of Jesus, authority and rights of leadership were passed on to him. When he was brutally murdered in 62 CE by the High Priest Ananus (see Josephus, Antiquities 20.197ff), Simeon, a second brother [“cousin” according to Hegesippus] of Jesus took over the leadership of the Jerusalem based movement. Clearly we have the idea here of a blood-line dynasty, and according to the Gospel of Thomas, discovered in 1946 in upper Egypt, this dynastic succession was ordained by Jesus himself who tells his followers who ask him who will lead them when he leaves: “No matter where you are, you are to go to James the Just, for whose sake heaven and earth came into being” (Gospel of Thomas 12, and additional primary texts here). Indeed, when Simeon was crucified by the Emperor Trajan around 106 C.E., one Judas, perhaps an aged third brother of Jesus, or at least a close relative of the bloodline, took over the leadership of the community.
.. Based on what we can reliably put together from these sources we can say the Ebionite or Nazarene movement could be distinguished by the following views:
1) Jesus as a human being with father and mother but designated a “Prophet like Moses,” or “the Anointed of the Spirit,” who will be revealed in power as the “Son of Man coming in the Clouds of heaven,” following his rejection and death (Acts 7:37; Luke 4:18-19; Mark 10:35-45; 13:26-27).
2) Disdain for eating meat and even the Temple slaughter of animals, preferring the ideals of the pre-Flood diet and what they took to be the original ideal of worship (see Genesis 9:1-5; Jeremiah 7:21-22; Isaiah 11:9; 66:1-4). This reflects a general interest in seeking the “Path” reflected in the pre-Sinai revelation, especially the time from Enoch to Noah. For example, divorce was shunned, as violating the Edenic ideal, even though technically it was later allowed by Moses (Mark 10:2-11).
3) Dedication to following the whole Torah, as applicable to Israel and to Gentiles, but through the “easy yoke” or the “Torah of liberty” of their Teacher Jesus, which emphasized the Spirit of the Biblical Prophets in a restoration of the “True Faith,” the Ancient Paths (Jeremiah 6:16; Matthew 11:28-30; James 2:8-13; Matthew 5:17-18; 9:13; 12:7), from which, by and large, they believed the establishment Jewish groups of 2nd Temple times had departed.
4) Rejection of the “doctrines and traditions” of men, which they believed had been added to the pure Torah of Moses, including scribal alterations of the texts of Scripture (Jeremiah 8:8).
Generally, the movement came to have a very negative view of Paul as an “apostate from the Torah,” though it is possible that in the 2nd and 3rd centuries there were branches of the Nazarenes who were more tolerant of Paul as the “apostle to the Gentiles,” but who as Jews, nonetheless, insisted on Torah observance.
He also has a video on this on YewTube.