Yes, the Nexus 6P and Nexus 5X will work on Verizon and Sprint
The official Nexus 6P and Nexus 5X specs lists (found on Google's website) confirm that the North American versions of the two devices support CDMA bands 0, 1, and 10, thus being compatible with all three CDMA carriers mentioned above. Basically, if you buy a Nexus 5X or Nexus 6P, you'll be able to use it on any US carrier, as the handsets support a wide variety of cellular bands (GSM, CDMA, WCDMA, LTE).
As a reminder, the Google Nexus 5X costs $379 (16 GB), or $429 (32 GB). Prices for the larger and more advanced Nexus 6P start at $499 (32 GB), going up to $549 for the 64 GB model, and to $649 for the 128 GB one. If you want to take a closer look at Google's new smartphones, check out our Nexus 5X hands-on, and our Nexus 6P hands-on.
source: Google (Nexus 6P, Nexus 5X)