We know how to make a emission free 2 stroke. They are called Container ship Diesels.

A 2 stroke with fuel injection & seperate crankase lubrcation does it without all the parts of 2 or 4 cam OHV setups. That is strictly for ego racing trips. OOHH AHHH !

Real life can do without OHV engines. There were many different 2 stroke Diesel designs invented in the 1930's thru 2008.

Which engine manufacturer is going to lay out the cost of retooling first for a new design and have everyone else copy it for free around the world.

You first. Not me.