I am very skeptical that Eastern Rite Catholics of any form would venerate any individual (in their liturgical worship or in their prayers or that they would encourage private veneration) who had not been raised to the office of Venerable, Blessed, or Saint by the authority of the Universal Magisterium of the One Holy, Catholic, and Apostolic Church through a decree by the Pope.
They do. I’ve seen it myself.

I’ve assisted at Divine Liturgy at a Byzantine Catholic parish on the second Sunday of Great Lent, and the liturgy and even homily did indeed focus on Saint Gregory Palamas.
Also, canonization by the pope is not the only way to be canonized. Canonization was a local process for many years. Plenty of saints (particularly early ones) haven’t been formally canonized by any pope.
And as
greigo catolico pointed out, the Catholic Church has an official listing that includes some post-Schism saints of the Orthodox churches.
I don’t think there is any reason to take my opinion personally as several seem to have done. Why does that occur so ofter on this forum? Why all this super sensitivity?
People are indeed very sensitive on these matters. I don’t think they’re wrong to be so, but it can be jarring at first to some.
And I would like to know by what authority post schism Eastern " Saints " are either still venerated in the liturgy of Eastern Catholic Churches or approved for private veneration? I don’t think this is unreasonable?
As others have said, these liturgical practices are officially approved by their bishops and synods. And the Holy See has never raised an objection as far as I know.
Im a little confused, guys. I know that several popes have declared that outside the catholic church, there is no salvation. And I know that many bishops still hold this teaching in the most strictest sense (which in my opinion is the most Orthodox belief). How then can the church allow the veneration of these saints?
Vatican II clarified this matter greatly: Christ’s Church on earth, as constituted into a visible institution, subsists specifically in the Catholic Church - that is, the communion of churches that are in communion with each other and with the bishop of Rome.
But “elements of truth and sanctification” (Vatican II’s phrase) can exist outside the
visible confines of the Church. That doesn’t mean that there’s salvation outside the Church; there’s not. But it does mean that if one accesses these “elements of truth and sanctification” in a salvific manner, he is inside the Church - because he is enjoying the fruits and the graces which flow from her alone -
without being a visible member of it.
It is basically certain that this is possible at least in the cases of the Orthodox churches, whose Sacraments, faith, and apostolic succession the Magisterium recognizes as legitimate.
This may sound like a novelty, but it’s not. The only premise is really depends on is that
one may be inside the Catholic Church without being a visible member of it, and this is true even from looking at pre-Vatican II teachings: for instance, baptism of blood or of desire. If a catechumen dies in true faith and desire for God, he is saved, even though he has not been baptized (which is normatively necessary for salvation) and is not actually a
member of the Church yet.
In fact, the Magisterium has been recognizing some heretic groups’ baptisms as valid since
at least the days of Pope St. Stephen. The fact that such a baptism can be valid proves that one can effectively be inside the Church - i.e. receive the grace of baptism, which comes only through the Church - without being a member, since those heretics were obviously
not members.
Anyway,
that’s why there’s more of a grey area than “no salvation outside the Church” seems to suggest at first glance. Of course, none of this should encourage indifferentism, either.