@michele654, you can try a “simple trick” to enforce the device-IC2 traffic going out via the SFC by setting up an Outbound (OBP) rule, similar as shown below.
You can choose either Algorithm = Priority or Enforced
Once the OBP rule activated, you will be able to know your B20X-“SFC” IP from the IC2 (sample below).
Do give it a try and let us know the outcome.