Orthodox certainly reject this heretical belief!
As far as I know, the Orthodox Church teaches the same thing the Roman Catholic Church teaches on this subject. I most certainly reject the serpent seed lie.
PS Eastern Orthodox clergy is valid clergy, and our Bishops have authority through Apostolic Succession just as yours do. Our sacraments are valid sacraments. Both Churches recognize that. Our Eucharist is a true Eucharist. There is no way that we could teach something like the serpent-seed lie and be an apostolic catholic Church, nor could our faith be orthodox.