I’m not sure if you’re looking at litterature in Japanese, but if English is OK, have you tried r/AskHistorians reading list? https://www.reddit.com/r/AskHistorians/wiki/books/eastasia#wiki_japan
Most of reddit is… reddit-like, but r/AskHistorians has, as far as I can tell (that is, unless there’s a giant conspiracy to make fake scholar profiles and disseminate false information on university websites), actual historians talking seriously about (not always) serious stuff.
I have at least (partially) read Japan Emerging and taken a look at some other books on the list, and from what I’ve seen, you won’t find nationalist propaganda in there. It’s written in an academic style, but academic history is far more accessible than some other disciplines, so it’s quite fine as it is IMO.