Juventus players are inexperienced or we are not saying that they will not be able to adapt to the team. Juventus' main weakness against Sassuolo is that some of their key players are injured. And against Sassuolo they won't be with the squad. And so it will not be easy for Juventus to win against Sassuolo. Although Sassuolo is not a strong team. Also, even though Pogba is experienced, don't expect him to adapt quickly to the team. Even after his long stay with Manchester United, his performance was not good.
Except with many player are injury and disallowed I think Juventus still have bigger problem on defender central position area, they have loss with Matthijs de Ligt after playing for Bayern Munich and right now Juventus not really focus for finding new replacement position leave by Matthijs de Ligt. I think with Leonardo Bonucci is not really enough depending he was 35 years old, I don't see about who will be partner for Bonucci after leaving by Chiellini and De Ligt because on defender position have option with Daniele Rugani, he looks active as substitutes player for Juventus than other before still finding new defender.
They lost Chiellini as well, De ligt, Demiral, all players who are central defenders, and they lost them all in a single season. I have to say it is not going to be easy for them to recover from this right away, you do not have a solid back just with one summer window after losing 3 of your most important players.
I kept saying they should have kept Demiral, a defense line with Demiral and De Ligt would have been amazing, and now they have neither instead. In any case, if they are really serious about the current situation, then they could get someone on a loan, wouldn't be permanent solution but at the very least they could pay a lot less with just a loan situation, and would benefit from it financially.