Actually what you are describing is a MIDI harp. There are a few makers who make MIDI harps in something closer to a lever harp form (Mountain Glenn and Kortier come to mind), and as mentioned Camac has made a workable MIDI Pedal Harp (although I believe it is not in general production).
The electroharp is something different. Several makers make electro harps, including Camac, Lyon and Healy, Kortier and Mountain Glenn, and a couple other makers. An electroharp is more like the harp version of a solid body guitar. No sound box. They use crystal pickups that are pressure sensitive to detect the vibration of the strings and convert them to electric signals that get run through an amplifier to be heard.
The differences between the two are, an electroharp still requires the use of a standard pitch changing system, either pedals, or levers, since like an electric guitar, the actual rate of vibration of the string determines the pitch produced. With a MIDI harp the string vibrating is a trigger, and transmits information about things like duration, dynamics, etc… but the actual sound is produced by a sound module of some kind and so the pitch is independent from the actual tuning of the string. Raising the pitch is a matter of signaling the sound module to play a different recorded pitch when the string is played.
A wah pedal or whammy bar wouldn’t work with a MIDI instrument. The whammy bar works by loosening and tightening the string, and since the tuning of the strings is irrelevant to the sound produced by a MIDI instrument a whammy bar wouldn’t work.
A guitar effects pedal works by manipulating the electric signal produced by an electric instrument. It works with an electric instrument, but not a MIDI instrument. MIDI instruments can mimic these effects, but that is done thorough a sound plug-in at the sound module and not by an actual effects pedal.
Think of it this way. An electric instrument still produces the vibrations that get converted to sound, they just take it through the additional steps of converting the vibrations to electric signals and then back to sound.
A MIDI instrument is just a triggering device. The sounds produced are triggered by it, but they are actually produced by a computer that holds pre-recorded sound samples that it plays.
That is why a MIDI instrument can look like anything (a harp, a recorder, a guitar, a keyboard…) and produce a sound like any other instruments or even non instruments (Jingle Bells barked by dogs for example). In fact they can do things other than just produce sounds. Play a specific string or key and instead of it playing a sound it can control a light (or do both at the same time). That’s why they are called MIDI controllers. They control other things. Most often a sound module, but they can control other things as well.
There is video on youtube of the Camac MIDI pedal harp being played here:
And of the Kortier MIDI harp being played here:
To see an electric harp check out Alan Stivell (who is pretty much one of the Godfathers of the electric harp) here:
And Deborah Henson-Conant here playing an electroharp with guitar effects pedals:
These are just examples to demonstrate the difference between a MIDI harp and an electroharp.