Curious, what kind of mistakes did you make? I've largely checked out of this whole shebang, so while I am vaguely aware that is an issue, I haven't seen any myself.
Things that should have been obvious to everyone is the promotion figurine featuring both Oda and Toyotomi family crests at the same time or the quadratic tatami mats in the trailer. You don't need an expert for that.
Many other things like the wrong era seiza, the Chinese architecture, the wrong kanji in promotion articles, the upside down crest in the trailer, using a One Piece sword instead of a historical one for the main character, the half tori gate inspired by the monument for nuclear bombing, that is all stuff that might not be as easy to recognize, but could have been avoided by the designer doing minimum work like the above mentioned google search.
Only for things like them using something that looks like a sepukku assistance as a fatal in combat maneuver, you would need an expert to know that it is actually really offensive, not just a bit silly.
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On the whole , so far only promotional material and trailers exist. The actual game
is not even out and trailers should be fine tuned for publicity. We have seen so little and so much of it is wrong.
And no, that is all independend of the disputed samurai-ness of Jasuke, that fake researcher scandal or how some people are hung up on his proclaimed bisexuality.
