Although Dortmund has better experience in the Champion League compared to PSV, but I think it still does not fully guarantee for Dortmund to be able to beat PSV . Indeed, Dortmund are in the hell group in the group stage but still, PSG and Milan also have a performance that is not completely stable at that moment. With this factor, then I cannot assume it is entirely possible about Dortmund being better than PSG and Milan.
After all, in this season the fact is that PSV also has very good results in the Eredivisie, because PSV managed to win all its matches in the first half of the season. Indeed, the results of matches in the domestic league cannot be fully used as a benchmark for their performance in the Champion League. But yes, at least with the good results PSV has in the domestic league is likely to make PSV's morale also remain good in the round of 16 against Dortmund later.
I think Dortmund have different mentality this season. They are good in Champions League, but scrumble in Bundesliga. They may still be carrying on the effect of last season failure. They look uninterest in the Bundesliga, but full motivated in Champions League. Dortmund have a better experience in the Champions League compared to PSV if we just count the latest Era, because PSV also have proper history in Champions league, But past experience alone doesn't guarantee success in a specific encounter.
PSV have a stable morale with doing excellent results in the Eredivisie and progressing to the round of 16. This aspect of them is better than Dortmund's, but the Champions League is a different competition with its own dynamics. No body had thought that Dortmund would do good at a tough group stage. I think Dortmund will show their best in Champions League to compesate their performance in Bundesliga.
Regardless of Dortmund's performance in qualifying for the round of 16 in a difficult group, Dortmund doesn't seem very reliable, especially considering the results of their last 6 matches in all competitions. Dortmund has never won in its last 6 matches, including the Bundesliga, Champions League group stage matches and also the DFB Cup. Therefore, I am not sure that Dortmund will go higher in the Champions League this season even if PSV is also not very hopeful.
In the Champions League, PSV and Dortmund both have the opportunity to qualify for the quarter-finals. PSV plays at home first and then visits Dortmund, but Dortmund is a team that may have a higher probability than PSV. I'm not sure about one of them, but Dortmund have good experience in the Champions League.
PSV's performance in the group stage matches was quite good. They lost just one match. They played against teams like Lens and Sevilla in the group stage. Dortmund's performance was not bad either. But now their performance is more weak. We haven't seen good performances from Dortmund players in the last few matches. Dortmund have dropped points in their last four games in the Bundesliga and are currently fifth in the table. Their performance has deteriorated significantly. And they won't be able to win against PSV if such erratic performances continue.