Building on the work of these and subsequent informal consultations, an official Joint Commission for Theological Dialogue Between the Orthodox Church and the Oriental Orthodox Churches began to meet in the 1980s. In its agreed statements on Christology, the Commission repeatedly and unequivocally affirmed the churches’ full agreement on the substance of the faith, notwithstanding differences in terminology. “In the light of our four unofficial consultations (1964, 1967, 1970, 1971) and our three official meetings which followed (1985, 1989, 1990), we have understood that both families have loyally maintained the authentic Orthodox Christological doctrine, and the unbroken continuity of the apostolic tradition, though they may have used Christological terms in different ways” (Chambesy 1993). Indeed, as the documents of the dialogue point out, “Our mutual agreement is not limited to Christology, but encompasses the whole faith of the one undivided Church of the early centuries” (Anba Bishoy 1980), including, for example, the veneration of icons. 
so both the OO and EO churches are right.
miaphytism (OO) is actually one person with two natures united into one 'without mingling, without confusion and without separation'
(the quote is from the coptic orthodox divine liturgy).
it does not contradict the chalcedonian view AS CLARIFIED BY THE 5TH AND 6TH COUNCILS.
it is a big, big subject to try to understand all these apparent word games, and you should know that there was a lot of politics involved at the 4th council, so that complicates things.
what i would really recommend for you is to pray (and fast) and ask God for guidance and then look for a church near you that is either EO or OO and see if the people there are ready to welcome you and to show you the depths of God's love found in the orthodox church.
the important things you should look for in an orthodox church are the love of God and the willingness and ability to explain orthodox Christianity to a visitor in a language he / she can understand.
whether the church is EO or OO is really secondary.