IMO, that is a composite wood siding. Some people call it hardboard. It is not cement fiber siding or sawn plank board. LP is a brand name, stay away from brand names unless you watched it come out of the package and installed in front of you or it is stamped.
Those cut edges should be painted.
In your final photo, that is OSB plywood (oriented strand board) and it is not exterior rated. It will deteriorate as installed.