What is the difference between vnf and switch in pipe mode?

According to the Flow programming guide, it describes vnf as “the packet arrives from one side of application, processed, and sent from the other side. The miss packet by default goes to the RSS of all queues.”
Does this mean the “missed packet” is processed by the application, while other packet goes by defined rules by default? What does the go to “RSS of all queues” mean? I assume it means on cores of RSS queues of a dpdk port.

And switch mode is defined as “used for internal switching, only representor supported. The missed packet is received on all RSS queues of the representor of the uplink.”

Is the difference between vnf and switch mode, in the difference of received on the “representor of uplink” or not?
Or is the difference in the “only representor port supported”, like the vnf is “only” supporting the “not” representor ports, for example PF/SF/VF?

The switch picture draws the packet goes to the DOCA_FLOW app, how is it different from “the packet arrives from one side of application, processed, and sent from the other side” in vnf?

Also the switch pictures shows “HOST/ARM”, but I assume the E-Switch is on the NIC, how can it be on host?

Do vnf and switch mode both involving hardware offloading? Do both involve E-switch on ConnectX adapter?

I run the simple_forward_vnf and doca_switch example, do they represent such differences?

So basically I still not understood the difference between vnf and switch mode. I would appreciate so much if someone could explain such long questions.