In this vein of low-hanging fruit, my former anesthesiology chair once remarked that you could build a first-class academic career in the specialty if you knew German and simply went through the 1900-1920 German physiology literature and gleaned significant findings unknown even now in the non-German-speaking world. Alas, my other language was Japanese.

Would Google translate be able to help or has German moved significantly in the meantime?

I definitely have the impression that many of the "low hanging fruits" are found at the intersection of disparate fields.

There are much more people highly proficient in a single field than mediocre in two different fields, so if you want to discover something new and important, look at a new field through the lens of one you're proficient in.