Easy Method to REMOVE Products from Categories in Bulk
There is no way to easily REMOVE products from any given category in bulk. It is possible to select-all and add to a category en masse, but there is no way to easily remove multiple items at a time.
Here's the solution: https://wordpress.org/plugins/bulk-remove-posts-from-category/
Thibault de Changy commented
This is so basically important.
You could for example add radio buttons to "add" OR "remove" selected categories.
I agree, bulk edt unslecek a category would be great