>>46902275OP here. Funny enough both playthroughs were completed by a group of fish who would be swapped every twelve hours for health stuff. Sapphire started with 4 fish and ended with 5, while leaf green started with the same 5 and ended with like 6-8.
>>46902467So in truth the game wasn't entirely played by the fish. During the fish switch, the owner would place the player to the farthest point that the fish got to, as to not have the fish loop around pallet town forever. He'd also backtrack to specific locations to encourage grinding. However he never went amy farther than the fish had gone. So basically they'd make baby steps every 12 hours.
Also I don't know this for sure, but I'm pretty positive that the owner would deposit or withdraw Pokemon in order to give the fish an actual team and not 6 butterfrees.