yes, but the key question in cases like this is who has to do the work? it looks like you could probably extract shapefiles from here (https://usgs.maps.arcgis.com/home/item.html?id=f158df0740cb4bd3b6171b28860dadd9) for conversion to kml.
that said, it looks like a fairly complex set of data, and each watershed boundary seems to be larger than Texas. so i doubt that even if someone took the time to try to load this data, that they could do it even after greatly simplifying the boundaries.
so it would probably take staff to do it, and judging by the progress on loading standard places for the world’s oceans (https://forum.inaturalist.org/t/implement-standard-marine-places-for-the-worlds-oceans/1458), i suspect that loading watersheds for the US would not be high on the list of things to do.