The image below is from Manuke FPS, the chapter shared this week. I don't know you, but I NEVER shake hands using the left. Not even when the right is dirty or hurt. Is this a japanese thing or a manga thing? Not the first manga I saw this...
Actually now that i think about it, most animes / manga i read that had hand shaking was done alternating both hands. Maybe it's just to show certain angles?
Maybe they don't care... You need to mirror the image to change the left to the right... It doesn't matter. The only way to change left to right is using a mirror.
There are some cases where the raws are coming from other countries. Usually the pages are mirrored. So some weird cases like this happen...
The whole shake with your right hand thing is due to the fact that most people are right handed. Before toilet paper and soap people would use their left hand and leaves to wipe their butts. There was always a good chance that a person had crap on their left hand at any given time, so the left hand became a taboo.
In my country because we read from left to right, 1 or 2 decade ago any manga that came here got converted. The publisher reverse the picture or mirrored like you say, its kinda funny if the text say left but the picture show the right. Detective Conan become the victim that i found. Nowadays, there are many manga that released in original format (read from right to left) so the confusion didn't happen again
I don't really ... care? Does it matter? Why does it matter? Why has it never mattered in my lifetime?