we're mirror twins. ENTP/INTP. It is possible as mitochondrial DNA could cause minute differences in genetically identical twins. The same way iris patterns and thumbprint patterns are different. Personality is too difficult to measure and quantify as directly due to genetics though.
I'd thought with fraternals, they would in effect be as distant from each other as a normal brother/sister, so the differences in personalities could be as wide as per normal siblings.