I just found in Catharina Elisabeth Brummer-26, at familysearch, that there was a text note with transcription from the MOOC death inventory (not the image). Interestingly, it also lists a few slaves as owned by the testator.
Wouldn't it be a good idea to systematically find these MOOC inventories at death, to check for ownership of slaves, and add them under a standard heading of 'Slave ownership' in the Biography?
This would help open up at least some minimal documentation of those slaves.
Another question: is there a place to look for slaves that were freed by their owners, or who bought themselves free, before slavery officially ended in the British Empire?