Well, it is IA who named it chick-o-pedia:
And we still don’t know how it will look or what info it will have.
Also, while killing the enemies with different weapons to discover weak points sounds pretty logical, it would be time-consuming. That’s because you would need to basically just defeat every enemy 14 times and you couldn’t do it in 1 mission (defeating every boss would need 18 stages right now and there are more bosses to come in the future).
There were many bestiaries in the games and I still didn’t see any being extremely awesome. Closest I can think of is Hollow Knight (not counting little story mistakes, but that’s debatable). In Hollow Knight you have bestiary and basic info about the enemy shows when you kill 1 enemy and you have the entry mastered when you kill specified number of them (+it gives you more LORE info), but you don’t have any statistics there. Also it’s in form of list which for me it’s a bad thing.
Terraria will also get bestiary in 1.4 and it looks like it could be great. Possibly even the best bestiary I ever seen in games. It has: +filters, +sorting by type, +icons grid view view, + shows stats of enemies, +is animated, +shows coin loot drops.
So yeah. Maybe CIU can have a masterpiece bestiary in the future. (but will it be useful?)