Anything that stops and starts each revolution cannot, by definition, affect "revability". Heavier pistons, for example, do take up kinetic energy, but do not contribute in any way to flywheel type inertia.

The fact that these two theoretical engines both made 120 hp means the kinetic energy loss is made up for by extra power being produced that doesn't make it to the crank.

Only part of the big end rod weight contributes to rotational inertia.

Things like alternators, which turn twice crank speed have far greater effect than timing gears, which turn at 1/2 crank speed. Smart to run a loose fan belt for this reason.

My bet would be on whichever had smaller CC intake & exhaust runners. Ability of engine to fill and empty on an increasing basis has been dubbed transient response by some of the smarter engine builders, notably Larry Widmer. It's a difficult concept to put into words.