You do have the differences between them and EO.
If I'm not mistaken, the Oriental Orthodox, who would avoid using the expression "two natures" and would instead say "one incarnate nature," also call Mary the mother of God. The justification for the title is not the two natures of Christ, but the hypostatic union.
The difference is really nominal. It comes down to saying that our Lord is from two natures rather than in two natures. The Oriental Orthodox fully agree with the Eastern Orthodox on the hypostatic union, the status of Christ as theanthropos, and that Christ is fully man and fully God without change, confusion, separation or division.
Also, one fact not well known among Eastern Orthodox is that the hymn Ho Monogenes, used by all Oriental Orthodox churches, and which I think is the best confessional hymn of Christological Orthodoxy, and which was added to the Eastern Orthodox liturgy by Emperor Justinian*, was actually written by Mor Severus of Antioch, which is why it opens the Syriac Orthodox liturgy**. Thus it is known among the Oriental Orthodox as “the Hymn of St. Severus”, except among the Armenians, for some of them also embrace apthartodocetism or something similiar, and so they attribute it to St. Athanasius the Great, which is not liturgiologically credible, as much as I love St. Athanasius as the Pillar of Orthodoxy and expect he would agree with it.***
Also the Oriental Orthodox have been blessed to not have experienced any of their churches from being hijacked by patriarchs who adhered to Iconoclasm, and also have always rejected Monothelitism.
* Justinian also championed Theopaschitism until for unknown reasons he embraced the widely discredited alternative of Apthartodocetism (which is not the same as Docetism, it is Chalcedon-compliant, but extremely complex, and I don’t know of any contemporary canonical Eastern Orthodox bishops who believe it).
** Thus we know it was not written by Justinian because of the violent reprisals conducted in his name against Syriac Orthodox bishops from Antioch, where only Mor Jacob bar Addai was able to avoid arrest.
*** Interestingly, there is an Eastern Orthodox version of the Athanasian Creed, which while not written by St. Athanasius, is largely a synthesis from two of his letters, and this version, which can be found in
A Psalter for Prayer, published by Holy Trinity Monastery (ROCOR) in Jordanville, is clearly the original, as it lacks the filioque. Not only is it found in Russian psalters, but Greek editions of the
Horologion also include it.