list your network locations:

  networksetup -listlocations

choose your desired network location:

  sudo networksetup -switchtolocation <locationofchoice>

list „devices“ called networkservices

  networksetup -listallnetworkservices

list persistent routes on „device“ of choice i.e. „Ethernet“

  networksetup -getadditionalroutes Ethernet

add your route to „Ethernet“

  sudo networksetup -setadditionalroutes Ethernet 192.168.1.0 255.255.255.0 10.0.0.2

list persistent routes on „Ethernet“ again to check

  networksetup -getadditionalroutes Ethernet

To see all commands:

  networksetup -help or
  networksetup -printcommands