Yes, Stephen Strange is the Sorcerer Supreme on the MCU.
This exchange from Hulk and The Ancient One on Endgame proves it.
Ancient One: It's the duty of the Sorcerer Supreme to protect the Time Stone."
Hulk: Then why the hell did Strange give it away?"
Ancient One: What did you say?
Hulk: Strange. He gave it away. He gave it to Thanos.
Yo me ...
At the moment, it's not entirely clear.
The Marvel Fandom page for the MCU version of Dr. Strange states that he is currently the Sorcerer Supreme:
Doctor Stephen Vincent Strange M.D., Ph.D is the Sorcerer Supreme and a Master of the Mystic Arts. Originally a brilliant, although arrogant, neurosurgeon, Strange got into a car accident which resulted with his ...
There’s more than one Dark Dimension in the multiverse.
surely, in an infinite multiverse, there will be at least one, if not an infinite number of dimensions/universes in which everything is almost exactly the same, with only small differences, for example the sky is a slightly different colour
Maybe, maybe not. We have a limited understanding of the ...
Strange is yet to become the Sorcerer Supreme in the MCU. At the end of Doctor Strange he has been made Master of the New York sanctum.
The Ancient One: You defended the New York Sanctum from attack. With its Master gone, it needs another, Master Strange.
It is later spelled out for us at the end of the film that the Sorcerer Supreme "...