I concur that Apple should just add support for Apple Pencil 2 in the Pro Series. An imperfect pencil charging might be achievable by reverse MagSafe at the MagSafe charging location on the iPhone Pro: place the iPhone face down and the pencil on the back.
Or just specify out a pencil charger. The third-party-device folks would have a dozen different chargers available in a month. My guess is that there are lots of folks like me who have been craving an Apple Pencil2 for the iPhone. My XL hands and fat fingers are just too large for ideal iPhone operation, especially the photo editing that I do a lot of.