Your first sentence covers it well, Correa is dealing with the defense alignment that all the coaches stick him with, they may not be forms that he flourished with in the past.
I still compare Correa to Simmons and Simmons range last year was HUGE, perhaps Correa's range is not as large and they are sticking him where he is most uncomfortable handi-capping his talent.
Without him the Twins would be in a world of hurt.