In the Bleak Midwinter (no lever flip version)
Strictly speaking, the lever flip is not the hardest thing in the piece. There are far more irksome instances of crossing under and changes in fingering to accommodate the coda.
However, if one wanted to avoid that lever flip, one could still get the effect in the coda of going into the relative minor by just replacing the C#-A in the left hand with the third space E and the D below it. That will get the idea across.
You will probably want to muffle the low D at the start of the next measure, or else you risk buzzing against it while reaching for the E. On every other instrument in the world, you spend your entire life trying to make the right noises. On the harp, you spend your life trying to avoid making the wrong ones.
Anyhow, just one more instance of Music Theory to the Rescue, in this case by enabling the playing of what amounts to chromatically modulating music while sticking to a diatonic scale. 🙂