I have a working prototype of the companion app running as a VST, but no concrete plans to release a VST.
That being said, SynthNes does support multiple Midi inputs and a lot of parameters are exposed to Midi CC. While not as convenient as a native VST interface, a Midi loop back can be set up to pump automation from a daw to SynthNes. If you watch the app UI in this video you'll see the channel parameters respond to the CC messages from Reaper:
If you do pick up a N8 and have any questions about SynthNes, feel free to ask!