I want to address this line first: τί γὰρ ἂν παθόντες δίκην τὴν ἀξίαν εἴησαν τῶν ἔργων δεδωκότες;
It means (very roughly) Suffering what penalty would match their bad deeds? i.e. How can such terrible deeds even have a properly awful punishment?
I can’t fit the Greek words together into a question. Should τῶν ἔργων be read as the genitive complement of ἀξίαν? How does the participle δεδωκότες fit in?
Lit. “Having suffered what (τί παθόντες) would they have paid the worthy penalty for such deeds?” The ἄν belongs to the periphrastic perfect optative εἴησαν δεδωκότες;
Is the second “ὧν” an instance of attraction to the case of the antecedent?
I’m having trouble identifying the scope of the negation οὐδ᾽ .
Lysias must be saying something like this: “Even if you wanted to inflict punishment extra-legally, you still could not make the punishment as horrible as the crimes.” However, I can’t read the sentence confidently to produce this.
παρ᾽ ὧν is “from whom” i.e. from those who destroyed the city.
And yes the ὧν in τῶν ἀδικημάτων ὧν τὴν πόλιν ἠδικήκασι is a case of relative attraction, ὧν representing ἂ. (He could equally well have abbreviated τῶν ἀδικημάτων ὧν to ὧν ἀδικημάτων, “what crimes”, incorporating the noun within the relative clause, but that would have been rather too casual perhaps, less impressive.)
As to the scope of οὐδ’ “not even,” logically the “not” applies to ἂν λάβοιτε, while the “even” applies to the participle. But we do just the same sort of thing in English.
So: ”… from whom not even if you were wanting to exact a punishment illegally could you exact one commensurate with the crimes they have committed against the city.”
We already dealt with the concluding sentence (τί γὰρ ἂν παθόντες δίκην τὴν ἀξίαν εἴησαν τῶν ἔργων δεδωκότες;), and you can see that this one has the same structure, fleshed out a little: first a participial phrase with βουλόμενοι, equivalent to a conditional clause (oὐδὲ παρανόμως βουλόμενοι δίκην λαμβάνειν ~ τί βουλόμενοι), then a potential optative (ἂν … [δίκην] ἀξίαν τῶν ἀδικημάτων ὧν τὴν πόλιν ἠδικήκασι λάβοιτε ~ ἂν … δίκην τὴν ἀξίαν εἴησαν τῶν ἔργων δεδωκότες).
Here too the ἄν gravitates towards the beginning of the sentence, as such little postpositives regularly do. Although it’s sandwiched within the participial phrase it belongs to the main clause, making it a potential optative. In such cases the ἄν is sometimes repeated in the main clause.
Plenty to chew on here! And there was an earlier thread on τοὺς οὐδὲν ἀδικοῦντας ἀκρίτους ἀπέκτειναν which you may have seen, preposterously drawn out as I remember. I’m glad we don’t have to spend more time on that!