This seems like a negligible cost. In my experience, both companies stick to a common system of measurement (almost always metric) and go on with life as normal

This seems like a negligible cost. In my experience, both companies stick to a common system of measurement (almost always metric) and go on with life as normal. It’s not like both companies maintain distinct engineering plans for their native measurement system and have to manually sync updates from each side, and almost any American company that regularly deals with International suppliers is already using metric domestically (e.g., anything in the automotive, construction, agriculture, forestry, etc equipment industries as well as anything in the electronics space, the energy industries, and so on).