I believe this study.
But travel by the Anglo-Saxons to England from Northern Germany is a much shorter route than the Etruscans would have to have taken. Also, the Anglo-Saxons themselves may have initially had some familiarity with the area by having been deliberately settled there as allied forces by the Romans.
I think perhaps the Etruscan ancestors were members of the Sea-Peoples who raided the Egyptian delta.
The Etruscans only had to traverse the Mediterranean, not the North Sea. In both cases, there was so much coming and going that knowledge of the territories was current and thorough.