As mentioned games don't really have any uniform concepts, and in this case no hardware derived concepts either outside of maybe some really old or really specific arcade stuff.
However, much like levels themselves, there are broad categories of things that devs do. Harvest moon I imagine (also from a quick scan of some footage) to be more of the teleporter variety (you step on/activate a pad which is an in game object no different than the other objects you can interact with) than the continuous level (various examples, varying from things like the Tony Hawk loading tunnels in American Wasteland to the likes of GTA's various levels of streaming as the franchise went on, though each may still have teleports for "indoor" events) or instanced level (think puzzle game where you have a menu between things).
In this case it is a full 3d game rather than the more classic 2d style of much of this series. This means you likely have the collision overlay to deal with -- most 3d is just a pretty picture, it is the "track data"/collision net that handles things, possibly with another for NPCs and in game items).
What said teleporter does is anybody's guess. You say you have location data which is potentially helpful -- some games might include a map number and location within it (or location of the world if this is one of those move the world rather than the player/camera deals), it might be that if you fire a number of your choosing into that value that it will take you there but other times it will only be for that map/room.
Cheat wise... for the PS2 then more than possibly and actually quite likely, though it may be a fiddly cheat to implement. For direct access cartridge systems (basically most things that are not the DS or newer than it) then everything usually gets loaded directly from the cart. For disc based devices and other slow read storage device, of which the PS2 is one, then everything tends to get copied to memory first. If it is in memory it opens up things for cheats, rather than read replacement options like game genies.
The trouble will likely come in said teleporters not being in a predictable place in memory, at least not between rooms. You might be able to treat your house/farm as a hub world and everything else happens randomly (or there is a random door in that). To do it for more than one room will likely leave you doing lots of if this then else that type cheats which are no fun to handle. Alternatively if it is that your location data is all powerful then you can try something with that and ignore the level aspects entirely.