PS4 Remote play does indeed still work, and there's about the same risk of ban as using any other homebrew on the Vita (which, so far, has been virtually 0).
If your PSN account isn't linked on your Vita, you'll need to use this:
http://wololo.net/2017/02/10/ps4rel...-without-psn-sign-now-automated-via-homebrew/ < To link it to Remote Play. Once done, then you can just enjoy PS4 Remote play as normal
Just note that it's still local only, and if it asks to update you can just hit cancel and continue on as normal.