There's no doubting the fact that Manchester City's performance in the UEFA Champions League this season is poor when compared to what we've been seeing from them since Pep Guardiola took over the managerial position at the club. That said, I think they'll travel Paris Saint Germaine with the sole intention of winning that game since they know their dreams of reaching the knockout stages might be dashed of they lose the game. Their hosts' chances of progressing to the next round is also uncertain at this moment so I expect both teams to give their best in search of all three points in that game.
You're right. Man City performance is declining a lot recently, it is both in UCL and EPL. In UCL, Man City is almost out of plays-off zone. Man City needs to win in the remaining matches if they want to finish in plays-off zone at least. If Man City has no problem in their preparation against PSG, I am very sure Man City will win the match. In the last 2 matches, Man City begins to show their good performance again. It is the time to show their good performance in UCL, too.