There's a website dedicated to the history of the institute.
(Website is naturally in German but you can click on the US/UK flag to read it in English)
'The Institute museum was the only one of its kind in the world. Thousands of photographs could be viewed there: pictures of sex criminals, neurotics, the mentally disturbed; pictures of eccentric sexual practices, perversions, and the instruments and tools used for them; historical photographs, entire files on brothels from all time periods and from throughout the world; photos of prostitutes, homosexual men, tranvestites, lesbians, exhibitionists, sadists, masochists, pimps, kleptomaniacs, and many, many more. ...
In short, all that was collected here was like a labyrinth of human passions and aberrations! We had countless objects that had served to satisfy sexual fetishisms: a collection of about a hundred pairs of women's kid leather shoes in all colors; boots, including some that were laced-up well past the thigh. In the same museum room there was an exhibition case filled with braids and locks of hair that one, single braid-cutter had cut off and collected. From a panty fetishist we inherited a selection of the most beautiful, varied, exquisite, and intimate pieces of lingerie that have ever been worn. ...
One of the strangest collections we had were the abortion instruments that women from all eras and peoples had used to perform abortions. The exhibition was rounded off with precise statistics that interested scholars from all over the world.
In a separate room, we had a sizable collection of pornographic books that spoke of healthy and sick love, in pictures and in writing, in prose and in verse, in all languages. . . ."'
https://www.hirschfeld.in-berlin.de/institut/en/ifsframe.html