I actually have a 2016 2.0Ghz MacBook Pro with Function Keys, and I purchased a 512GB SSD from a 2017 MacBook Pro with Function Keys and tried swapping them. The 2017 doesn't work in the 2016. Can't tell why either. Doesn't show up in the disk utility, although a bunch of little tiny disks did in Terminal's disk utility after I did a diskutil list. Update (07/19/2018): Well, I should update this-- turns out the 2017 SSD that I had used had been fried. I had replaced my 2016 one with a different 2017 SSD and it turned out to be perfectly good! Just be careful when installing and removing the SSD, apparently it can short against the board when pulling it out.