In a 2016 interview with Lufia & the Fortress of Doom's director Masahide Miyata, he was asked where the Japanese name 'Estpolis Denki' (Japanese for Biography of Estpolis) comes from. He responded:

"Estopolis Denki was originally developed under the title “Esuteeru”, but someone had already taken out the copyright for that name, so we had to change it. We chose Estopolis since the root of the word resembled Esuteeru. Estopolis means “City of the East”, and we imagined this world having four continents, in the east, west, north, and south."
Contributed by ProtoSnake