Earth-47 is home to two creations of Joe Simon, who is most famous for co-creating Captain America for Marvel Comics. BROTHER POWER THE GEEK from 1963 and PREZ from 1973 took place on this world. Brother Power in particular is infamously considered by many to be one of the absolute worst comic books ever made, being cancelled after only two issues.
The Love Syndicate of Dreamworld, who also exist on Earth-47, were originally from the 1990 story PURIFICATION DAY by Grant Morrison. There, they were creations of the villain Psycho-Pirate.