Marc,

Manual levers are more forgiving of grind settings since you can adjust your pull to compensate. I switch back and forth from pour-over to espresso with my old Vario, doing 90% pour-over, I'd give it a go, have the grinder running when adjusting and I find that the settings are much more consistent when you always adjust finer, so if I'm going from an espresso session on the weekend back to pour-over (midpoint on my Macro scale) I'll adjust the macro setting all the way coarse while the grinder is running and then come back to my preferred setting. This works as the adjustable burr rests on top of the adjustment plate and only the force of gravity pulls the lower burr down so it can be possible to have the burr not all the way down to it's setting.

I"ll bite on the question. Can you switch between ? Yes. Can it be done easily and consistently? No way. Easily would be owning two different dedicated grinders as previously stated.

Had a vario for press and not happy with the results at all. I was switching between for a while, and that was 2x bad. Even when just using as a brew grinder, in my opinion, the Vario AP creates an inconsistent grind with fines at course settings.

I have a virtuoso now that blows away the brew cups I was getting with my vario. That said, I also have a dedicated espresso grinder because switching back and forth was a huge waste of coffee.... For me..

Depends what you mean by switch easily. French press hates fines and espresso loves fines. It's easy to switch the grind settings if the hopper is empty, but you'll always have the leftover fines from espresso when you make a french press. Switching from french to espresso shouldn't be a problem as long as you put a few beans through to purge out any remaining pieces. If you don't keep the hopper empty, then you'd be wasting a lot of beans as you need to have the machine grinding while adjusting the fineness/coarseness. Typically going from fine to coarse doesn't need the motor running, however, the lower burr (the burr that gets adjusted) doesnt go down unless the motor is running. You can pull the lever down to coarse, and then physically push the burr down without the machine running but it won't go down on its own while off.