Strongly recommended but not strictly required. Without them you manually jog the wire to your work-zero before each cut (we have a setting for that: "Machine has no homing switches" in Settings → Machine type, which omits the G92 zero-axes line from the G-code).
Mechanical microswitches (€1 each) on the X / Y / U / V min limits are the cheap path. TMC2209 sensorless homing skips the switches entirely (uses motor back-EMF to detect collision) but needs careful current tuning.
Mechanical microswitches (€1 each) on the X / Y / U / V min limits are the cheap path. TMC2209 sensorless homing skips the switches entirely (uses motor back-EMF to detect collision) but needs careful current tuning.