In "Codecs" -> "Raw video" need P010 & P016 support. Otherwise ffdshow can not act as a filter for Hi10P video.
The filters inside ffdshow do not support those colorspaces.
Then is it possible to do so would ffdshow not get loaded when the source offers such a color space? Because otherwise it is changed to another color space and color loss.
There are no developers available that are interested in doing this. In fact, there are currently no developers working on ffdshow at all.
There is very little loss in quality when using a different colorspace, because dithering is used when converting. The similar conversion that is eventually done during rendering by madVR.