I would not classify either of the 7.63 mm Mauser rounds with the heavy, dual square primer crimps, one with a ring and one without, as Japanese. Both types have been found in Italy, but that alone doesn’t guarantee Italian manufacture either.
They are not Japanese. The Japanese 7.63 mm Mauser (and 7.65 mm Parabellum) have a distinctly Japanese look to them when viewing the head. The primers are domed brass cups seated deeply in the head; that is, the highest point of the cup is slightly below the case head. There is no visible primer crimp of any type on either caliber. Oddly for Japanese rounds, the bullets are CNCS (magnetic) FMJ RN. They are held in place by the three stab-type crimps common to Japanese Pistol ammunition. The cases are brass, of course.
Once seen, the Japanese ones are hard to miss when encountered, which unfortunately, is almost never.
I have classified the one with the two square primer crimps as being of Italian manufacture almost solely on anecdotal advice from other knowledgable collectors. I am not totally confident with that type of identification, though. Box labels are best, or factory drawings showing the features in question. I have still left the one with the two crimps and the rings shown as “unknown manufacturer.”