@UchihaKyu beyond a name drop here or there in Chobits there isn't any meaningful direct connection between the two other than the technology used to create the Angelic Layer toys being scaled up create the persocoms of Chobits. The former was developed for an entirely different purpose than what the persocoms are though- the latter's creation was repurposing the data collected from the former.
Icchan is the big connector between the two series an important character to the overall narrative in both stories but his roles in each are generally speaking unrelated to each other:
creator of Angelic Layer, as a funding project to develop sophisticated prosthetic limbs; and the 'father' of Chi
. It does extend beyond him simply being a character in both stories
someone's who's read further can maybe comment, but from comparing Ch.1 it looks like the Manga Daisuki one has a more "in context" translation and better typesetting, KSS one translates more (including effects) and seemed more "literal".
Going with Manga Daisuki one since the typesetting is more pleasing to look at for this childhood nostalgia journey
It's been so long so I might remember it wrong, but I wonder why in the anime, they had to swap the pair. I prefer the manga though, the relationship here is... very CLAMP.