Most crossgrained means contrary or stubborn, so the antonyms for this phrase would be cooperative, agreeable, and compliant. A person who is crossgrained might be unyielding or difficult to work with, so antonyms for this could be easygoing, helpful, or supportive. Instead of being unaccommodating, someone who is accommodating or adaptable would be the opposite of most crossgrained. Instead of being obstinate or headstrong, someone who is acquiescent or pliable could be viewed as the antonym for most crossgrained. In summary, the antonyms for most crossgrained are cooperative, agreeable, compliant, easygoing, supportive, accommodating, adaptable, acquiescent, and pliable.