Did two online chats and one phone call with Project Fi support. All three said "NO" to my answer. They said the memos they received said that Verizon-sold Pixel phones would not work with Project Fi. However, none of them could tell me what was so "special" about the Verizon version.
which makes absolutely no sense to me... Verizon smartphones are not SIM-locked to begin with. I have AT&T and T-Mobile SIM cards inside my Verizon S7 and Verizon Note 7 phones. Sometimes I also put FreedomPop SIM cards in those Verizon phones. All work perfectly.
unless it's some software that's lacking in the Verizon Pixel phone? (not that Verizon is actually actively blocking it... just the lack of the right software to work with Project Fi?)