First off I’ll just enumerate some existing systems and the components (and data) they need, and output.
Drawing: coordinates, Sprite, doesn’t write game state
AI(might have multiple flavors): goal, coordinates, scent, vision, sounds, outputs a goal
movement: goal, action pool, updates action pool, coordinates, other entities
trap effects: coordinates, ballistics or melee target, target entity updated
Cruise control? vehicle physics, vehicle throttle, writes to vehicle throttle
Engine tick: engine stats, vehicle throttle, fuel tanks, writes to vehicle physics and fuel tanks
vehicle movement: vehicle physics, vehicle coordinates, writes to vehicle coordinates, triggers collisions (that have to happen synchronously unfortunately)
Note on application of damage, it might be better to spawn damage-causing effects as a side effect of other actions, and apply them in a later phase instead of applying it immediately, in which case:
damage application: damage details, resistances, writes to health object
Systems it probably doesn’t make sense to turn into ECS:
Scent diffusion
FoV calculation