This is a posable action figure from the Nendoroid series.
From the Good Smile Company website:
From the popular browser and smartphone game "Touken Ranbu -ONLINE-" comes a Nendoroid of the Bizen sword, Uguisumaru! He comes with three face plates including a standard face, a combat face as well as a smiling expression based on his "sometimes it's good to take it easy" line from the game.
His sword can be displayed both sheathed or drawn allowing you to recreate various scenes from the game, and he also comes with parts that were seen in the 1st anniversary celebration illustration. Be sure to add him to your collection!