地味な剣聖はそれでも最強です
Translates via Google Translate to
Splendid sword is still the strongest
So that's one mystery solved,
@Moodyz.
Edit: I gave it a try. Basically, the title is stating that he looks like any other swordsman, but he's really the strongest. So... the hook here for this Isekai might be that he's a boring kid and might have asked for superpowers... but still looks like a boring kid? Looks kinda like he's going to have a family, so maybe there's some sort of politics or somesuch?