It had been established that Cisco designed the pipeline cells as dampeners to prevent prisoners from using their powers. Although unable to break out, Dinah is shown using her Canary Cry while imprisoned.
Overgirl tells Supergirl that she was fortunate to have her space capsule land in the Fatherland. At the time her capsule landed (decades after the Axis won), the entire WORLD would have been considered "the Fatherland."
When Green Arrow, White Canary, Citizen Cold and Alex Danvers attack the Portal compound on Earth-X, while shooting, the drawstring for Oliver's bow disappears each time an arrow is fired. This is due to the CGI used.