Is anybody using, or know if it's possible to use, FaceFx 2017 with UE 4.15?
If you are using FaceFX 2017, you MUST use the 1.3 version of the FaceFX Runtime binaries to compile the files. This is the first version that supports the FaceFX 2017 .facefx format.
Once you have compiled the runtime files, you can use them with any of the UE4 plugins built with version 1.2 or 1.3 of the FaceFX Runtime. UE4.15 has a pre-compiled plugin for both 1.2 and 1.3, so you might as well use the 1.3 version.
Obviously both FaceFX 2015 and FaceFX 2017 can export FBX files which can be used by UE4 as well.