What happened between Laporte and City is fairly straightforward and somewhat overblown. He was on the cusp of signing however was actually out, at the time, with a lengthy injury and was tempted to stay and recover by Valverde who was a father figure. The latter moved on to Barca and, while Laporte was initially hopeful he might follow, the immovable and irreplaceable force known as Samuel Umtiti happened and effectively rules out any chance he'll be reunited with Valverde.
So now he's no longer injured and stuck playing for a club who's style no longer suits him and who have no hope of taking his game forward. Every single post match interview that he gets questioned in, to this day, there is something in there about Pep and City. He continues to follow and retweet Pep on Twitter and has, as far as I know, always left the door open for a move here even when he extended with Bilbao. He has talked about moving since April 2017 and made it sound almost a certainty, to the point most Athletic fans are no longer surprised by the idea. So I think it's safe to assume the player almost certainly wants, and feels ready for, the move.
The only question is if City still want him. He is the best, perhaps only, fit for a long term partner to Stones at the back. His skillset is absolutely unique and perfect for Pep's possession/passing game and he is already, on his best form, a defensive upgrade over say Evans (though I'd argue JFE is a pretty consistent 7/10 which has its advantages also)
All that said, since we extended Nico, and given our recent policy, I'm not sure I'm ready to buy into any hype yet.