HP number may be the same, however the prop power curve is what matters (torque and RPM). A motor that makes 250 HP at 6000 RPM (218 lb ft), however hast a steep power curve ) best for a light, fast hull) has a different use than a motor that make 500 lb ft of torque At 2500 RPM, that gradually drops off as RPM rises holding 250 HP from 2500 RPM thru 4500 RPM (Best for towing, or larger heavier boats and hole shots)
So to answer your question, yes and no. 250hp = 250hp. However Horsepower is defined as the amount torque at a particular RPM (HP=Torque x RPM/5250)
The power curve for a 2-stroke is different than a 4-stroke than a diesel, than an electric.
The right motor must match the application, or overall performance is dismal.
I would not use a 250hp outboard on a 40,000 houseboat, and I would not use a 250hp diesel IO on a small 16' 400# fishing boat. The prop curve demand for each application would not be matched to the torque curve available from the motors
