This Alexei vinyl figure is released by Funko in their POP! Marvel x Black Widow vinyl figure series.
Funko POP! is a crossover vinyl figure series by Funko and other famous franchises such as Disney, Pixar, DC Comics, Marvel Comics, Simpsons, South Park, Uglydoll, etc. Each POP! figure is about ~3" to ~5" tall and crafted in a Japanese anime/manga super-deformed style (NOTE: due to the unique design of each character, the actual size of the figures may be smaller or bigger than stated).
The POP! Marvel x Black Widow series features characters from the superhero film that follows Black Widow (aka Natasha Romanova). At birth the Black Widow is given to the KGB, which grooms her to become its ultimate operative. When the U.S.S.R. breaks up, the government tries to kill her as the action moves to present-day New York, where she is a freelance operative.