I am struggling with understanding get vs be:
He is so slow, he will get hit by the ball.
He is so slow, he will be hit by the ball.
It is the same? I know that get can replace be or indicate change of state/condition.
In this context, the word get means
This becoming sense is closely related to the simple future tense of to be in your examples.
This even works in the past tense
This usage of get is often followed by reflexive pronouns such as himself, yourself, myself.
While your two sentences can be viewed as equivalent, some might read a slight suggestion that get hit implies some personal involvement or causation.
seems to subtly suggest more culpability than