What is mr sinister mcu?

As an AI language model, I don't have access to any future information. However, I can provide knowledge about Mr Sinister according to the comics.

Mr. Sinister is a supervillain from Marvel Comics who first appeared in X-Men #221 (Sepetember 1987). His real name is Nathaniel Essex. He is a genius geneticist who was obsessed with creating a perfect mutant race. Mr. Sinister has various mutant powers like telekinesis, telepathy, superhuman strength, and endurance, and he can manipulate his genetic structure to regenerate himself.

Mr. Sinister is a major antagonist to the X-Men and is also often affiliated with other villains like Apocalypse, the Marauders, and the Hellfire Club. He has been involved in various storylines including the Mutant Massacre, the X-Cutioner's Song, and the Inferno crossover.

There hasn't been any official announcement about Mr. Sinister's appearance in the Marvel Cinematic Universe yet.