I examined this since 2017 when I produced the TOS Ent Chair.
Not going to explain the detail, just sit down on your chair and cross your leg and look at the following picture.
Examine your own body and you will see all the circled areas need to give way or change shapes inorder to do a cross leg posture. (I am talking about the thigh against thigh cross leg. Angle on knee cross leg is not difficult)
Therefore, it is NOT possible for action figures to have this posture even extending the hip joint wouldn't work (Simple and Easy body has hip joint extensions just like SHF and Mafex).
This is why there are statues.
Either you do it right or don't do it at all. The only way to have a non Toyish and natural looking cross leg posture is statue.
We can make the lower part of the body as One piece to make this natural.
Then we are doing hybrid like HT super posing figures that they had years ago.
Action figures have limitation. Expecting anything beyond the limitation is unrealistic. Only statue can satisfy your expectation.
I don't think I missed anything but the Nemesis Uniform suggestion mentioned else where in the thread.
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