I spent a couple minutes searching and i cant find anything about that. That would be some pretty cool lore and go a ways to explain why humans are compatable with so many species. I did find some sources that state that humans were their preferred slaves, and that they massively helped humanity by taking their slaves all across the galaxy during a time when the infinite empire was the only group to have hyperdrive tech. Humans were working to colonise their solar system and the surrounding areas when we got conquered by the rakatans. It is worth noting that coruscant is the cannonical home world of humans in star wars, which means the rakatans at one point conquered coruscant. It’s also worth noting that “Earth” does exist in legends lore, han solo goes to Earth and i think he fights dinosaurs, i cant remember.