Complex sentence: In certain styles, Pinan Shodan and Pinan Nidan are inverted-what certain styles call Pinan Shodan is what others call Pinan Nidan, and vice-versa.
Split into simpler sentences: In certain styles, Pinan Shodan and Pinan Nidan are inverted. That is, what certain styles call Pinan Shodan is what others call Pinan Nidan, and vice-versa.