I agree with you, even though Barcelona is the favorite in the match against Napoli, this will not necessarily match expectations because Barcelona is in an unstable condition and Napoli is not an easy team and of course this will be a match that is difficult to predict because the performance of both teams is the same. the same is not very consistent in the domestic league, but even so, I hope Barcelona can win this match because in my opinion, even though Barcelona is unstable, I hope Barcelona can appear surprising in the next match even though they have to fight hard because the first match will be held at Napoli headquarters.
The match between PSG vs Real Sociedad is indeed a match that must be watched carefully because this match is very important for both of them, but even so, it looks like PSG will remain the favorite here because PSG has shown progress, especially in the domestic league, its performance is still consistent, for Real Sociedad this is This is their first time competing in the Champions League but Real Sociedad was able to qualify for the round of 16. This is a good start and now they have to fight hard against a team that has more experience competing in the Champions League.
Between Napoli and Barcelona currently, there's no much difference because both teams have flaws they're battling with. For Barcelona, they're not so grounded yet as there's a bit of shakiness and inconsistencies in their usual performances before now. They're now at a low leveled performance phase than they are normally known for.
For Napoli, the team just got a new boss and so Mazarri is trying hard to implement strategies that best fits his team and would give them the required results. There are still weeks to the round of 16 games, so it's more chance given to both teams to improve themselves in their various league games and then be better prepared for the encounter in February, judging both teams, they've got same odds of qualification based on the current teams' technicality.