Transmitting Rotation by Two Slider-Crank Mechanisms

There are two identical slider-crank mechanisms. Their positions in relation with the slider centerline are identical too.
Input: the pink crank rotating regularly.
Output: the violet crank.
Rotation direction of the output crank depends on its start position.
- If the two cranks rotate in opposite directions, the output crank rotates regularly as per this video.
- If the two cranks rotate in the same direction, the output crank rotates irregularly.
This phenomeno has been seen for parallelogram and anti-paralellogram mechanisms.
Measure to overcome dead points for the output crank is necessary (not shown).
This mechanism shows that slider-slider mechanisms can transmit rotary motion between two skew shafts of large center distance, subject to slider length. However the slider large inertia is a problem.
The revolution joint (in orange) between two sliders is for easy setting relative position of two crank shafts.