Yes, 4-stroke engines are overhead valve (OHC) engines. At the same time, OHC engines can operate on a 2-srtoke cycle. The cams, valves, & ignition all just cycle every cycle instead of every other. Transfer port style engines are dedicated 2-stroke. Everyone calls OHV 4-strokes & TP 2-strokes because of the normal association of each to the respective operating principle. A true TP style V12 would really be something else.
A few years back during the SCCA Runoffs at Indy, we pitted a few stalls over in Gasoline Alley from them. Jason and I were talking about the engine and its unique design. That was the first time I saw a 2T in a full sized race car. I was in awe of the six tuned pipes sticking out the back and it was a rocket on the straights.
GM built more large two-strokes than anyone else; the 71 series engine for road use had half the bore and half the stroke of the 567 for rail and sea.
A spectacular example of the smaller units is this 12V53TT: 12v53
This EMD F7 has a 16-567 with Roots blowers: 16-567
The smaller engines are only built for military use, but Progress Rail (Caterpillar) still builds the 710 for locomotives - after 80 years the two-stroke is still preferred for rapid acceleration and low fuel consumption.