I like writing with you, because I find you to be reflective and open to considering the EO POV.
There are three issues here:
Whether violence was inflicted at Ephesus II itself, were declarations threatening violence used, and was Ephesus II and its leaders responsible for Flavian's death.
The only moment I noticed at Chalcedon alleging violence there was where eastern bishops announced " force was used, force with blows."
Regarding the demands for violence, you wrote:
You just answered your question. Curiously, none of the hearsay participants mentioned that Eusebius was "cut in two" or "burned". Dioscorus used similar language against Eutyches in Chalcedon when the charge of Monophysitism was implied. These are hyperbolic proclamations by men to prove how seriously Orthodox they were. But that's it. They were noise, not blood. The allegations of violence were all refuted in Chalcedon. The best they could do was depose Dioscorus of the triple summons rule. That's it. The charges of murder or violence were unfounded.
Did you know Nestorius was deposed to the harshest desert in Egypt? All of his works burned, and retaliations were all boisterous. If Nestorius died along the way to Egypt, perhaps he too would have been a martyr to the cause, and people would have cried foul against Cyril's "violence". Oh but instead of Nestorius, let's use the case of Hypatia against Cyril as well.
What I see you saying is that when Ephesus II collectively shouted "Destroy and burn Eusebius. Let him be burnt alive. Let him be cut in two. As he has divided, let him be divided", they only announced this as hyperbole, and didn't intend for their opponents to be scared into submission on hearing the threats. Likewise, when the OO St. Barsaumus said " "He who says two natures should be cut in two", he didn't believe that the EO heretics were actually deserving of being literally killed.
If I accept this, wouldn't it imply that the Chalcedonians who claimed they were scared by these words into signing were lying or exaggerating, since they would have understood this as hyperbole?
Chalcedon recorded this discussion and refutation of the threats made at Ephesus II collectively:
Theodore the most devout bishop of Claudiopolis in Isauria said:
‘Dioscorus and Juvenal and all those who signed first .... to frighten us, they invoked as similar the heresy of
Nestorius, shouting at us, ‘Cut into two those who say two natures! Cleave, kill, and drive out those who say two!’ – so that, out of fear of the Nestorian heresy, we would not be judged orthodox but condemned as heretics.
... Dioscorus and Juvenal – accompanied by a mob of disorderly people, with a mass of them shouting and making a tumult and disrupting the council. ... They made sport of our lives. ... They terrified us.
The most devout Egyptian bishops and those with them exclaimed:
‘A Christian fears no one. An orthodox fears no one. Bring fire, and we shall learn. If they had feared men, there would never have been martyrs.’
The refutation here, of the EOs' claim of fear of the mob shouting for their deaths, is that a real Christian shouldn't fear anyone because then there would have been no martyrs, and that the OOs will withstand fire.
So this raises some questions:
Did they mean their refutation literally, as if a true Christian truly fears no one, even fire and martyrdom, or did they just see their ability to withstand martyrdom as mere rhetoric? In other words, aren't they trying to show their dedication to their doctrines by saying they would withstand real martyrdom, and contrasting it with their opponents' declarations of fear of their mob threats? If the mob had only meant it as nonviolent hyperbole, wouldn't they have chosen to explain that in their refutation instead?