How has akainu shown that he can kill kaido in power when his magma couldnt even affect shanks sword???
Of course if shanks vs akainu death match happen, akainu will break shanks sword because he has superior haki in his body . He can block Whitebeard attack with his body. Not weapon.
Try block dog attack with your body.
‘Now try to block with your object like sword, shield against dog.
‘Blocking with weapon is easier and less painful than your usimg your body to block attacks.
kaido body got hurt by kinmeon and made him bleed.
‘Akainu> kinemon
Therefore akainu can kill kaido and he is stronger than wano arc zoro.