Yontou-ryuu no Saikyou Haishin-sha: Yari Konda VR Game no Settei ge Genjitsu Sekai ni Hanei Sareta node, Haishi Yotei Datta Job de Musou Shimasu

Hayate is a solo player in the popular VR game Farum World Online (FWO), who excels with the unusual fighting style known as "Four Sword Style." However, he receives the terrible news that "Four Sword Style" will be abolished. Depressed by the news that "Four Sword Style" will no longer be available in the next update, Hayate retires from FWO after fighting alongside Elena, an archer and daughter of a wealthy family. However, the next day, the settings of FWO are synchronized with reality, and dungeons appear all over the world. While even special forces from various countries struggle to conquer the dungeons, Hayate's journey through a beginner's dungeon is broadcast to the world...

(Source: Natalie, translated)