There's no specific mapping for moderators, but a WordPress editor will be assigned as a Q2A editor as well. Here's the relevant code from qa-external-users-wp.php:
if (current_user_can('administrator'))
$level=QA_USER_LEVEL_ADMIN;
elseif (current_user_can('editor'))
$level=QA_USER_LEVEL_EDITOR;
elseif (current_user_can('contributor'))
$level=QA_USER_LEVEL_EXPERT;
else
$level=QA_USER_LEVEL_BASIC;
current_user_can(...) is a WordPress function.