No, it's not possible to search by genre on the BM5/BS5.
And it's so frustrating that such a simple feature is not available in BM5. I have asked B&O a couple of times and the answer is that this is a feature that they do not intend to support.There was no explanation just that this is a decision made by the development team, and that is the way it is and will continue to be.
I'm listening mainly to classical music and not having the ability to search for, for instance, "Opera" is really a disadvantage. The fact that they do not intend to implement a more advanced search function, which I know is smth. that many users want, makes me doubt B&O's dedication to this system.
"Creation 5" has just been updated and this will do want you want. However, BS5 is created with the near-control experience in mind and "Creation 5" cannot replace that.