I checked all the items, and the added stats are all correct. However, I found that when you give the cross to the fairy, she increases your stats, and this time it is a percentage increase. Since there are no prompts for this in the game, you might have misunderstood. (Spoiler: it increases by 33%)
I submitted a new version(v1.1.1) with the corresponding prompts and also fixed some missing localizations, hope it can help you.