Dortmund lost their best player upon the closure of the season 21/22. Haaland left for Man City. But while he was still at BVB he was obviously the best selling player at their store.
In the German Bundesliga they wear a league badge to the right arm sleeve.
And from another angle. Where the sponsorlogo to the left arm sleeve is also clearly visible. Car manufacturer Opel seems to be shirt sleeve sponsor.