Dizzy would be the main thing that will stop you car from starting when wet, red circle, i normally cover it in a plastic bag and still avoid spraying the area, also don't let much water get down the pluglead holes, red oval.
Any electrical connections are going to be possible issues if you drench them, blue circles, avoid directly spraying any that you see.
Yellow circle is the air intake, it's mostly uphill from there so should be fine unless you spray high pressure straight up it.
There's ther things but i ca't really circle everything, leads to your throttle body, injectors, ect ect should all be not subjected to high pressure.
You really are opening up alot of potential problems by spraying the motor with high pressure, electrical issues caused could be intermittent and hard to track. At most i would use a gardern hose or spray bottle to move degreaser, but honestly lots of rags and elbow grease, some degreaser and then some sort of shiny spray are safer options.
