You could put a right-side drive crank on the left, but you would need to loc-tite in the pedal to keep it from unthreading. And clipless pedals are basically undoable too.

Or, you could get a left side drive crank for a tandem. Then the pedal will say it, and clipless is doable. But, you don't get the tiny-ass chainwheel of the trials cranks.