The Champions League has different pressures, equalising the EPL and UCL I don't think is appropriate. I know Tuchel is the defending champion but Anceloti he has more experience at UCL. The first leg may be chelsea will dominate with their trademark short uphill and possession. They certainly have a better mentality because they play at Stamford Bridge. But remember the second leg they will play at the Santiago Bernabeu. Of course a draw in the first leg and winning in the second leg is my prediction for Madrid.
It may go similarly with the previous match of PSG and also Real Madrid where Real Madrid may be defeated or under pressure in the first leg. But commonly an epic comes back to Real Madrid and will give certain surprise again to them, moreover when they are playing at home. This will really give big opportunities for Real Madrid to play more powerfully and optimally, in front of their big fans.
That is why it may be still difficult again to redict which is better and has higher chance to win. Chelsea cannot be underestmated, so does the Real Madrid.
Chelsea versus Real Madrid fixture is definitely a 50-50 chance but I am going to lean towards the side of Chelsea mainly because they are seems to have inculcate the winning mentality in the team even at the face of adversity, they have been playing well and winning games as if the club is not under pressure from the government and football organizations. I doubt if Real Madrid team is as strong mentally as Chelsea.