I see there's a new Holocaust Handbooks volume. HH #54, The Confessions of Kurt Gerstein by Henri Roques. This is Roques's thesis from the 1980s, so it is not exactly new, but it is back in print and in a new edition. Gerstein now has the honor of having two dedicated Handbooks volumes.
https://holocausthandbooks.com/book/the ... -gerstein/
There's also a new series, "Holocaust Pocketbooks." These are evidently intended to be short, accessible volumes.
Vol 1 - Rudolf, Nazi Gas Chambers: The Roots of the Story
Vol 2 - Rudolf, The Holocaust: Proven at Nuremberg?
Vol 3 - Rudolf, Bungled: Denying the Holocaust
Vol 4 - Mattogno, A Three-Quarter Century of a Propaganda
The Nuremberg book is recent and the first book is from last year. The other two are older. But having these as a series appears to be a new thing. And it looks like this series will have free pdfs available as with the Handbooks series. The two newest ones are under two-hundred pages, with generous fonts and margins, so probably novella-length in terms of word count.