"It’s reasonably obvious that if you are going to pump that piston up and down, you might as well get work out of it every time the piston comes down rather than every other time the piston comes down," he said.
Modern, direct injection, 2 strokes are pretty clean. You can blow the air in, rather than compress it in the crankcases and use a fuel injector. Or simpler, just use crankcase compression for the air & use a computer controlled oil pump to add the right amount of oil direct to the bottom end.
In either case you don't add fuel until after the exhaust port has closed, so no unburnt hydrocarbons going straight through to the exhaust.
My 1927 Scott has deflector pistons. A bit like a ski ramp on top of the pistons, so the incoming charge gets sent up into the dome of the head, rather than rushing across the piston and out the exhaust. Designed long before they understood about tuned length exhausts etc.
Evinrude E-tec, Mercury Optimax outboards have a similar system
Most of it stemmed from the Orbital Engine Company started by Ralph Sarich in 1972 Perth W Australia
it was based on the Wankel Rotary engine found in RX-5, 7 etc, an engine was not really produced, the engine could never be properly lubricated or cooled, it could also be driven by air or steam and used as a pump, however the combustion process Orbital Combustion Process was produced
OCP was fitted to the 3 cylinder Suzuki 2 stroke car engines, after that Sarich built his own engine, it produced 67kW but only weighed 41kg, it produced more power than GM's 1.6L 4 stroke J engine that weighed 128kg
From memory he sold off the rights to Mercury Marine, OMC (Evinrude/Can Am if you like), VW did some trials as did Fiat, the OCP was also installed in Aprilia two stroke scooters
The intellectual property made Sarich a very rich man, as far as I know no reliable Orbital engine was ever produced