Complex sentence: They felt that it would be inappropriate to revise the works, because Tezuka was passed and there was no way to reverse what he created, and revising his works would violate his right as a creator.
Split into simpler sentences: They felt that it would be inappropriate to revise the works, because Tezuka has passed away and there was no way to reverse what he created. In addition, revising his works would violate his right as a creator.