People confuse these two words and use adverse when they mean averse.
EG: I’m not
adverse averse to a good argument.
Use averse when you want to say someone is against something or disinclined to do something. It describes a person’s attitude.
EG: He’s risk-averse. I’m not averse to a good argument.
Use adverse when you could use negative or unfavorable instead.
EG. She had an adverse [negative] reaction to the drug. They faced adverse [unfavorable] weather conditions.