Robin Nano v3.1 + 3Dtouch + SmartFilamentSensor, USB connection

Since I use my Anet A8 Plus (upgraded with Robin Nano v3.1 + TMC2209 + Wifi + TS35 v2 Touchscreen) a lot, I'd like to upgrade it using

1. 3Dtouch
2. Bigtreetech Smart Filament Sensor V2.0
3. USB connection

1. The 3D touch is already mounted, but not connected, since I wasn't shure if I'd need a voltage devider. Not as I'm sure I need to add one, it's time to get into it.
I'd also like to keep the z-endstop for safety reasons (probably one day I'll start a print and the 3Dtouch won't work properly...so I'd like the printer so stop moving z-axis 1mm below bed, to prevent it from bigger damage).
So how would I need to connect the 3Dtouch and what would I have to setup in the firmware?

2. Also I'd like to use a Smart Filament Sensor.
Looks like it can be powered by 3.3V as well as 5V. Since the Robin nano v3.1 uses a STm32, I'll need to go for the 3.3V.
But how should I connect it to the board and what do I need to config in the firmware?

3. When I connect the Robin Nano v3.1 using a USB cable, it won't respond to any serial commands.
I think this depends on the config, since there seems to be some hassle with the comports.
I'm using the wifi module - so would I be able to connect it via USB anyway?
I'd like to read the config - just for backup reason. Also I might need to access the comport via USB one day - not yet important, but worth some work.
For the moment I connect Cura with Robin using the MKS wifi plugin. It works somehow...but it also has some bugs.
Once a print is finished, I need to restart Cura as well as the printer, to get another printjob started. Also uploading large files using wifi takes some time (about 100kb/s) - maybe using USB it would be faster.
So any chance I could use USB along wifi?

3) Its a serial port, -1

In Configuration.h you have to have
one of these SERIAL_PORT , SERIAL_PORT_2 or SERIAL_PORT_3 set to -1

There's one port set to -1, but I didn't have success.
Probably this one is used by the wifi module?

I'd rather like to access config commands and settings by ssh, since my printer now moved 4m far away from my computer. So if possible, I'd prefer ssh or something like this using wifi.

// @section machine

/**
 * Select the serial port on the board to use for communication with the host.
 * This allows the connection of wireless adapters (for instance) to non-default port pins.
 * Serial port -1 is the USB emulated serial port, if available.
 * Note: The first serial port (-1 or 0) will always be used by the Arduino bootloader.
 *
 * :[-1, 0, 1, 2, 3, 4, 5, 6, 7]
 */
#define SERIAL_PORT -1

/**
 * Serial Port Baud Rate
 * This is the default communication speed for all serial ports.
 * Set the baud rate defaults for additional serial ports below.
 *
 * 250000 works in most cases, but you might try a lower speed if
 * you commonly experience drop-outs during host printing.
 * You may try up to 1000000 to speed up SD file transfer.
 *
 * :[2400, 9600, 19200, 38400, 57600, 115200, 250000, 500000, 1000000]
 */
#define BAUDRATE 115200
//#define BAUD_RATE_GCODE     // Enable G-code M575 to set the baud rate

/**
 * Select a secondary serial port on the board to use for communication with the host.
 * Currently Ethernet (-2) is only supported on Teensy 4.1 boards.
 * :[-2, -1, 0, 1, 2, 3, 4, 5, 6, 7]
 */
//#define SERIAL_PORT_2 1
//#define BAUDRATE_2 250000   // Enable to override BAUDRATE

/**
 * Select a third serial port on the board to use for communication with the host.
 * Currently only supported for AVR, DUE, LPC1768/9 and STM32/STM32F1
 * :[-1, 0, 1, 2, 3, 4, 5, 6, 7]
 */
//#define SERIAL_PORT_3 1
//#define BAUDRATE_3 250000   // Enable to override BAUDRATE

// Enable the Bluetooth serial interface on AT90USB devices
//#define BLUETOOTH

// Choose the name from boards.h that matches your setup
#ifndef MOTHERBOARD
  #define MOTHERBOARD BOARD_MKS_ROBIN_NANO_V3
#endif

Also uncommenting the other serial ports leads to other issues (screenshots attached).