Great question and I’m sure there are many resources online with studies. I’m only guessing but while i think they could easily learn how to move pieces, They may not be able to comprehend the logic and reasoning behind the most basic elements of the game. This may be an interesting thread, thanks for posting!
how much time do you think it would take you to teach a baby chess

For me I think About 5 years to teach a baby chess but won't be easy you would need to tell them a bunch about chess to make them interested.This was a hard questoin to anserw

Depends on which baby/child. Everyone is different and although many behaviors are learned at that young age, they do have their own personalities and preferences. The is no way of really knowing for sure how interested they will become in chess a few years down the road (and how "good" they may become is an even tougher prediction), but naturally they will perform better if they love chess.
Maybe at this age, you can be more of a role model: if they see you playing chess, then they might be more inclined to try it themselves - even if only through emulation and not really understanding the game.
I think about 3 years what do you think? It would be great to know!