If you export an invisible VRM model (basically your model, but without the body mesh visible) and use that in VTuber Plus you can get the effects by themselves, and then in OBS overlay it on top of your Luppet model. It's not as good as using VTuber Plus directly and it requires a bit of tweaking/lining things up, but it's one possible solution.
I definitely recommend using VSeeFace though.