Nothing is preventing one to add a picture style for LV focusing only and then switch to an apptopriate style to make the photo.
The least trouble while shooting is to create a custom Picture Control, shoot NEF and then switch the PC in post. I do this anyway as I strip the sharpening when developing as the Standard PC may sharpen fine details too much with D800 NEF(s). A final step usually in Photoshop is to apply sharpening for the image's intended use just before exporting to JPG or TIF. I generally do not save the sharpening with the original PSD file. If a JPG is needed soon after shooting a JPG can be created in camera from an NEF. If it's needed immediately one would need to change the PC for LV focus and then again for shooting.
If there is a problem with histogram this can be reduced by maxing the sharpening of the Standard PC without other changes then saving it in Manage Picture Controls in the Shooting Menu. For cameras that offer Clarity in the PC pumping it up might help. I can't test this as my cameras don't support Clarity in camera while CNX-D does in post. I used C9 custom setting for an LV, PC with my D800. The D800 doesn't have the best Live View (It's really rather poor). Using a Neutral or Flat PC in camera is going to make the LV image really mushy. If an image needs highlight recovery I'll usually switch the PC to a custom PC I call Neutral -Sharp or I might go all the way to Flat -Sharp. Right now I'm developing NEF(s) about 90% of the time in CaptureNX-D and finishing up in Photoshop.
Dave