The premise of Superman becoming a Green Lantern on Krypton was visited in mainstream continuity. In JLA #8-9, the supervillain known as the Key traps the Justice League in their own private dreamworlds using a neural virus.
This idea of Superman becoming a Green Lantern on Krypton was explored in mainstream continuity. The supervillain the Key confines the Justice League to their own personal dreamworlds using a neural virus, similar to how the villainous entity known as the Key traps characters in their own subconscious realms.