Council of Trent, doctrine of Original Sin:
“If any one asserts, that the prevarication of Adam injured himself alone, and not his
posterity; and that the holiness and justice, received of God, which he lost, he lost for
himself alone, and not for us also; or that he, being defiled by the sin of disobedience, has
only transfused death, and pains of the body, into the whole human race, but not sin also,
which is the death of the soul; let him be anathema:”
“If any one denies, that infants, newly born from their mothers’ wombs, even though
they be sprung from baptized parents, are to be baptized; or says that they are baptized
indeed for the remission of sins, but that they derive nothing of original sin from Adam,
which has need of being expiated by the laver of regeneration for the obtaining life
everlasting,–whence it follows as a consequence, that in them the form of baptism, for the
remission of sins, is understood to be not true, but false, --let him be anathema.”
"If any one denies, that, by the grace of our Lord Jesus Christ, which is conferred in
baptism, the guilt of original sin is remitted; or even asserts that the whole of that which
has the true and proper nature of sin is not taken away; but says that it is only raised, or not
imputed; let him be anathema."
It doesn’t matter if you say the guilt is personal or not - the Orthodox reject the inheritance of the guilt of the Original Sin and we reject that Baptism exists to clean the guilt of the Original Sin.
We don’t know if sins will be forgiven after death - it’s a debate. Even the Aerial Toll House Theory is a debate. And it isn’t through some form of physical punishment that sins are cleansed, which is what Purgatory is described as.
There is one visible Church of Orthodoxy - period. From the Orthodox perspective, no - the Orientals don’t have Sacraments, as they are outside the Communion of the Church. On a personal level, one may believe that it is possible for such churches to have Sacraments, but dogmatically - absolutely not. It’s like how we can personally have hope that Judas Iscariot isn’t in hell, or how we can pray to non-canonized people (if we believe them representative of Christian living), or have a hope nobody is in hell. But the Roman Catholic Church dogmatically says that certain sects have valid but illicit Sacraments; i.e., actual effective Sacraments outside the Church, which is against the Orthodox understanding of it.
Interesting point nonetheless - however, the way you understand “imperfect communion” is heretical from both a Roman Catholic and Orthodox perspective. You can’t partially be a part of Christ, or select and choose.
“Whoever is not with me is against me, and whoever gathers not with me scatters.”
You are either with Him or against Him.
Let me explain why you are wrong from both a Roman perspective and an Orthodox perspective.