An 01 Forester is about as archaic an engine management system as there is in an OBD II car. There is not much more data available in the factory SSM2 and SSM3 scan tools than there is in global OBD II. Bidirectional controls are also nonexistant on a subaru of that vintage, connecting the green d-check connectors under the dash puts the car into dealer check mode which cycles all of the PCM outputs for testing.
FreeSSM and the correct cable is about the best you can do on this, @Timmastertech is right. It’s a simple system and not much monitoring. You can use ELM327 but what exactly are you aiming to do with this?
Indeed, the best bidirectional you can get is the plug under the dash. Used it several times myself, almost always for EVAP of course. A URaBus of this era will force you to speak EVAP in short order, like dropping you in a foreign country you must learn the language quickly