I have 1x4" pine floors in my kitchen and after I saw the Amish floors that they do hand scraping on. I want to do that to my floor now and wonder if anyone has done that to floors that have already been installed.
I have seen such floors too. I suspect the Amish have special scrapers for such things and you might see if they sell them. If you have an Amish community near you? Stop in to one of the farms, furniture stores, etc. and chat. They are nice people and anxious to share what they know if asked. You might also ask what they would charge to come in and do the project for you? There are Amish construction crews and related craftsman that do work around Central Illinois. Nice work too.
Pine can be soft so approach this project with caution. I suspect it takes some practice and skill to achieve the finish you have seen. I am not sure how it works if you already have a finish on your floors.