Japan coins obverse / reverse faces definition [opgelost]

Hello,
Depending on the website, obverse and reverse faces of japaneese Showa coins are inverted, for exemple this 1 Sen from year 16 to 18 that is not in the same order on wiki and others coin-collectors websites

Is there specific rule for obverse/reverse definition ?

This is all I know:

In Japan, from 1897 to the end of World War II, the following informal conventions existed:

the Chrysanthemum Throne (or Chrysanthemum Crest), representing the imperial family, appeared on all coins, and this side was regarded as the obverse;
the other side, on which the date appeared, was regarded as the reverse.

The Chrysanthemum Crest was no longer used after the war, and so (equally informally):

the side on which the date appears continues to be regarded as the reverse;
the side without the date is regarded as the obverse.

And because we now could change re- and obverse more easily I asked if the Numista rule (issuer identification shall be obverse, which I followed for all post Meiji-restauration coins) superseeds other ones.
https://en.numista.com/forum/topic72388.html

your explanation looks admissible.
I've tried the new inversion tool for the coin above, but the referee needs also to switch comments
Well, I should have done this switch