From the Washington Post:
For his own part, Todd told The Post he didn’t think of the odd nickname as anti-Semitic. “I’ve never taken it that way. If it is a slur, I’ve never heard of it,” Todd said.
Peter Kenez, an emeritus professor at the University of California at Santa Cruz who survived the Holocaust and went on to become a historian of the atrocities he witnessed, wrote about the “sleepy eyes” stereotype in one of his books. However, he thinks it is very unlikely that Trump knows about it, or that he picked up the term from one of his advisers.
Instead, Kenez said, it is probably just a coincidence that Trump uses the same nickname for Todd.
“I doubt that Trump knows what he’s talking about. . . . [‘Sleepy eyes’] was hardly a major feature of Nazi propaganda. It was not something that every German had to know,” Kenez said. Other stereotypes were far more common in Nazi Germany, he said. “I think it is too obscure. Our president has to have it to think up an adjective for everyone that he says something bad about. I suppose nothing else came to him.”