Convert stock Niro L1 charger to L2? No
Some L1 chargers reportedly can be converted to L2 simply by connecting the L1 neutral wire to the other hot2 wire of a 240V circuit.
L1 120. neutral, hot1, ground
L2 240, hot2, hot1, ground
Note: the Niro stock evse specifically warns against this.
Some evse circuit diagrams show the neutral wire connected to the output relay only, not connected to any circuitry inside the evse. The evse is powered by the hot1 and ground wires. If done this way, it is possible to see how simply connecting hot2 to the normally neutral wire would work.
However, the niro stock evse does in fact use the neutral wire to power the evse electronics. It is not a simple passthrough. I determined this by disconnected the neutral wire and seeing that the evse did not function.
2018 Niro PHEV LX Silver/charcoal