The BD tag indicates this is from the official Japanese Blu-ray release.
"The Girl's Truth" (or "The Empire's Assassin Blade" depending on the translation). Key Character: Lux Arcadia. Plot Focus: Lux confronts truths about the old empire and his past. [Witanime.com] SMNB EP 11 BD-HD.mp4
Witanime.com is a popular Arabic-language anime community and streaming site that provides subtitles for various series. The BD tag indicates this is from the