Older Characters in the game talk all about Hoenn. For Example, In Courmarine Town's hotel, an elder mentions a hot spring next to a Pokémon center, possibly referring to Lavaridge. And, in one town(I forgot) there's a man trying to sound hip and saying a phrase that makes no sense, possibly referring to the house of so-called "trendy people". The guy outside(in R/S/E) asks you what phrase is trending and then the whole family adopts it. (Mine was "Magikarp joking") And there are countless other hints!