They definitely skip over WW2 a lot, except if it’s specifically about the atomic bombing like in Barefoot Gen, but there are a handful of stuff from Taisho period (1912-1926) and that time period is seeing a bit of a revival in at least the live action sense, mostly from the fashion.
Imperial Japan also started in the late 1800’s with the Meiji period, which only the early years are romanticized about because of the identity crisis they were going through. The Taisho period is kind of forgotten about because it was sandwiched between two really big periods in their history.
They do show it with live action stuff, but not much with anime. It’s possible it has to do with exporting it to other countries, so you wanna show off “the cool stuff”.
Me being an American, our movies and shows targeted at kids tend to skip over almost anything in regards to Native Americans, and we don’t really see much from Europe in regards to the scramble for Africa, and that colonial period.