The weird thing with MS..

[Uzumaki Ray]

Why do some people who awaken the MS have same set of abilities while some get unique ones?
Sasuke got the same ones as Itachi and not even the Tsukiyomi.While Obito got the killer Kamui,Shisui got Kotoamatsukami solo,Madara got Shattered Heaven..

 

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[Kαmi]

Well Sasuke and Itachi are brothers to each other so that might have something to do with it. I've also seen a few theories in the past that imply that Uchiha awaken their type of ability based off the conditions they awaken them in. Like Obito wanting to create his own world was able to unlock Kamui and its world. Stuff like that.

 

[Seventh Sama]

Because the uchiha clan is the creators pet.

 

[Madaras torso]

shattered heaven is a rinnegan tech

 

[JustAnotherNarutoFan]

There are some theories but nothing else, Kishi wasn't specific about those abilities. If I had to guess one could go with the saying "The eyes are the mirror of the soul.".