For NA Horde, please feel free to join Horde Farmers Union - it has over 200 toons on the list and is for lvl17,22,24/25, farmer toons for farming Classic, MOP, Legion, and BFA BOE gear appropriate for lvl20 twinks. You can also park any of your toons there to keep an eye on any farming sessions.
Unfortunately the code is not static, but If you're on any of the Horde20s Community channels, please pm Supacow/Invisabull, Gogotank, Hashfarmers, Farmtruck/Polemistis, or Clinkz. Or you can ask around for the invite link since tons of people have their farmer alts in it.