Telling someone “just speak Japanese and blend in!” is sort of an absurd suggestion. That is impossible if you’re not East Asian and even if you are, it would take years of study.
You can still blend in far more than most tourists do by a) watching the people around you, and b) being a little bit self-conscious.
It's absolutely astounding how much tourists stand out in Japan (or Paris, or London, or New York...), and it's mostly about their behavior and clothing. Ten minutes of internet research and a little bit of introspection would go a long way to solving both problems.
Demanding the locals to accommodate your lazyness is basically shouting "I'm entitled".
Clothing and makeup is a better giveaway than facial features or skin tone, but even that is becoming harder with K-pop creating a pan-Asian style to aspire to.