Craft essences

so, today i just found something. i give an example :

i have three hero ce from sanzang event and hallowen princess ce with iri pics ( i like it. okay, nvm) and i have both of them on level 23, with stat based we all know that those ce added atk and hp altogether. at first i think the ce stats is same for evey ce on the game ( either it increased atk/hp/both) with the same amount. but i found that on current level ( level 23/100) :

three heroes ce gives 666 atk 416 hp
haloween princess ce gives 624 atk 416 hp

(EDITED) the question is, do craft essences same rarity have different growth stat in mid level?

sorry for long post, thx