If you're looking for manga similar to Occult Gear Overdrive (Light Novel), you might like these titles.
Imperial Galactic Army Officer Alan Corinth’s ship is seriously damaged after being ambushed by an unknown foe in hyperspace. Even though it was through sheer coincidence, he became the sole survivor. The stricken ship fell to the planet below. Alan alone managed to get to an escape pod. Alan the Imperial Army Officer wagers his survival in this savage world on the symbiotic nanomachines (nanom) in his body. The world he landed on was home to a prosperous human civilization, which seemed to have a strangely similar genetic pedigree to himself. In this puzzling fantasy world of swords and sorcery, Alan will live to the fullest alongside his comrades. What will Alan achieve in this strange world? A Science Fiction Fantasy in a Middle Ages setting starts here.
Tsukishiro Kotone doesn’t consider herself much of a gamer. That is, until she’s introduced to the virtual reality game “Free Life Fantasy Online,” also known as FLFO, by her game-savvy sister. In FLFO, Kotone decides to become a Zombie, one of the game’s inhuman races–a race that’s said to be quite difficult to master, even for experienced players. Why not, right? When Kotone embarks on her first quest in the darkness of the catacombs, controlling a fascinating undead body, little does she know that this game is about to become a huge part of her real life. Join the virtual adventure in this gaming tale about an online world like no other!