As Donna says, no one knows. Most of us don't find the IN store very profitable, but we're mostly writing in English. And KDP publishing is not nearly as profitable today as it was five or six years ago, before Select broke the mold.
(Don't trust KDP to publish a print edition. Don't trust CreateSpace to publish an ebook. Each does one thing well and the other thing poorly.)
This is something you can try and work out for yourself as the query is very niche. First, search for such books on Amazon. Make a list and note the date and their ranking. Go back to the list regularly and note the ranking again. There are some online tools which will give you an approximation of their sales by the rank. The one I use is on the kindleprenuer site.