Both teams have good results in the previous rounds, Freiburg won from Osnabruck with a score of 0 - 4 & Hamburger SV won from Meppen with a score of 1 - 7. With both results, this match will certainly be interesting. Bookies show that Freiburg is more favored, probably because of the difference in leagues that both teams play.
Freiburg will certainly be favored in this match, especially because they are acting as hosts. Although in their last match they lost in the Bundesliga, in this match they will certainly repeat their victory like the previous round in the DFB. Because as you said, both teams are also in different league castes. So this victory is important for Freiburg so that they can gain confidence again before facing Mainz 05 in the Bundesliga later.
Hamburger is indeed not an easy team, especially since they appeared very impressive in the first round of the DFB-Pokal, but in this match it is difficult to see how they can overcome Freiburg who are at a higher level than them. So my prediction is that this match will be tight even though in the end Freiburg will win this match. My Score Prediction Freiburg 2-1 Hamburger