Hi there,
If a user creates a blog post, only the owner of the post, super user or moderator can edit/delete the blog post(provided the permissions are set). The same goes for team blog. If a member creates a blog post, only the person who created the post, moderator and super user will have the ability to edit/delete the post.

FYI, there is only one type of moderator, which is a moderator that moderates the whole site. Therefore, it is not possible to assign a moderator that has moderator permissions within a particular teamblog only.
Hope this answers your question.