We've fixed both of those typos and the special skill names in the 1.1 patch, but we don't have any Indonesian members of the group. I'm not certain who made the first transliteration of that name, but it's the same sylables in Japanese, so it was presumably a choice by the devs.
I honestly have very little idea what natures effect. I believe it can have some effect on the results of training, I would expect a hardy Digimon to get a boost to Defense training for instance, but I can't confirm that.
I did mention this in the info post Sporky the nature affects stuff like training results, still testing if it has any effects on battles and skill learning.
You're right, my partner gets +20 DEF in intermediate training (plus training manual)