> I just wish they were intelligent enough so we could ask them not to stand on our clothes.
Just because they don’t speak our language doesn’t mean they aren’t intelligent enough to understand. This seems like a case for basic training and positive reinforcement.
You can try setting up an alternative perch for them. Then when you see crows on that perch, go over and feed them something they like. But offer it only to those on the “right” perch, not the ones on the clotheslines. They should be quick to pick up the rule.
But you may start to get other crows coming over too, so unless you have dreams of becoming a Disney princess or Marvel villain, perhaps consult with a professional first.