Tenka Musou Once Moe, 天下無双ワンスモア, 天下無双ワンスモア～異世界の老剣士、転生して最強ショタとなる～

Golden Era, Year 874... Mifune Siegfried, an unrivaled samurai, had dedicated 80 years of his life to the relentless pursuit of the sword. In his final years, he secluded himself deep in the mountains, where his life seemingly came to a quiet end in solitude... Or so it appeared! Finding himself at the start of a second life, he decides to aim for the pinnacle of swordsmanship once again! A cheat-level swordplay saga in another world begins!!