Why is BLTouch Still Probing Off the Bed Even When `NOZZLE_TO_PROBE_OFFSET` is Set?
Did you load the values from firmware after the re-flash? Use M502 to load the values you changed, otherwise it will keep using those from memory. Also set #define Z_SAFE_HOMING, then it will home in the middle of the bed.
Also, with a new carriage for the Hemera, your nozzle is not/might not be in exactly the same position as before as I learned from other adopters, you then should also need to redefine the offsets, see How to center my prints on the build platform? (Re-calibrate homing offset).