Some versions of isekai manga have (light beams, black bars) vs. uncensored (full art) editions. If you’re looking for uncensored volumes 1 & 2 of a specific “engineering isekai” series, check:

For a long time, the isekai genre focused entirely on pure power fantasies. A regular high school student or exhausted office worker would die, meet a god, and receive ultimate magical powers. Today, the trend points toward the complete subversion of those rules. The Rise of Bizarre and Useless Skills

The story starts in a familiar, yet inverted, isekai fashion. One ordinary day, a high school loner named Haruka finds his entire class suddenly summoned to a fantasy world by its god. The god explains that the students have been chosen to become heroes and must defeat a demon lord. As a reward, each student is allowed to pick one powerful special skill.