Muzokusei Mahou tte Jimi desu ka?: "Hadesa ga Nai" to Misuterareta Shounen wa Saihate no Ryouchi de Jiyuu ni Kurasu

I, a corporate slave who had given up on life, fell unconscious one day in an accident—and somehow my consciousness was transferred to Royce, the youngest son of a noble family in another world! According to Royce's memories that came back to me, he could only use plain, non-elemental magic and had despaired of life due to being neglected by his family...
"This time, I'm going to start my life over!" With that resolve, I persuaded my father to let me inherit an uninhabited frontier territory and became its lord. And as I began to hone my non-elemental magic, I discovered its true, extraordinary power—!?

(Source: AlphaPolis, translated)