You can use direwolf as well as a software TNC for PCs or RPis, I've been wanting to get this totally working with my Kenwood TR-2500 and a laptop PC but have been sidetracked trying to get a GPS working for the laptop... I got a few packets through to the APRS system successfully though it was a bit finicky with volume adjustments, of which a hardware accessory TNC would share similar issues.
The good thing about the Baofeng is that it supports VOX that the TR-2500 does not. That means I have to build some sort of computer controlled PTT on TX circuitry for the TR-2500, but VOX circuitry is a lot simpler than a whole hardware TNC at least...