They gave a summary of their differences in approach on the now defunct website. They see the two as complementary:
>Orthodox Christians, both lay and clergy, may wonder how the EOB (Eastern/ Greek Orthodox Bible) compares with the OSB (Orthodox Study Bible), and indeed if there is competition or complementarity between the two.
>It is important to understand that the main purpose of the EOB is different than that of the OSB.
>The Orthodox Study Bible (New Testament and New Testament part of the Complete Edition) is not an Orthodox translation of the ecclesiastical Greek Orthodox text - it is a special edition of the New King James translation (copyright control by Thomas Nelson) designed to help "find Orthodox Christianity in the pages of the New Testament." It is especially helpful as an introductory tools to introduce other Christians, especially Protestants, to Orthodoxy. Hence, the OSB NT contains many explanatory and interpretive footnotes, although some of them are possibly problematic.
>The EOB documents a few instances where sound Eastern Orthodox scholarship would not necessary agree with the OSB footnotes, as in Acts and Revelation.
>Moreover, it is presented to the English-speaking Orthodox community as an encouragement to study the Greek language and to produce a common New Testament text for Eastern Orthodoxy in North America.
>The scholarly bent of the EOB is evident in the articles included in the Introduction and Appendices, which cover fewer topics but with a more in-depth approach.
>the EOB and OSB are truly complementary editions of the Holy Scriptures for Orthodox Christians who are encouraged to use and promote both and to participate in the ongoing improvement process of the EOB.
It seems to have fallen into obscurity as a result of the OT not coming to fruition, although the NT was finalized and published. I've yet to see an equivalent translation of the Septuagint between the old Brenton version (and multiple revisions of it), the NETS (which is a revision of the NRSV), and the one in the OSB. I haven't seen the Lexham English Septuagint but if the Lexham English Bible is anything to go by their translation department is comprised of modernist Protestant scholars.