Quick question:  How gentle of a pitch bend do you have in mind?

The Vibrato algorithm (Manual assigned to an expression pedal) just might do it for fractional-semitone bends.  The H910 / H949 [Modern – Splice; Pitch Control – Smooth] can be used for much larger bends, but it’ll also go ‘gentle’.  Keep in mind (with the latter) the MIX will have to be 100, and your tone will change.

As for the pedal steel comment, it reminded me of these presets.  One uses PitchFlex; the other two HarModulator.

https://www.eventideaudio.com/forums/topic/whammy-bend-up-effect-help/#post-143611

https://www.eventideaudio.com/forums/topic/h9-presets-share/#post-138664

Those last two presets have envelope control, based on your signal input.  But that mapping can easily be adapted for expression pedal use.