@Manta for the Suunto plus app you have to compile and transfer this: https://github.com/SellA/BoschEBikeSuunto
In my opinion however this is not convenient since you have to do it from the pc and, everytime you sync with the Suunto App on the phone, it will be erased. That’s a “stupid” limitation on the Suunto plus app that are not official distributed trough the mainline channel.
I find myself perfectly happy with the ESP32 firmware flashed and set to POWER+CADENCE mode where i get the Cadence in RPM and Power in WATT. This is done trough standard communication like all other sensors and can be used without a custom plus app in the watch. And moreover, the power and cadence data will be used for Suunto internal algorithm, they are also correctly mapped to Strava if you have it.
I’ve connected my board directly to the motor for getting power (using a DC-DC converter to step down the voltage from 12V to 3,3V) and it turns on directly with the ebike. Low power port (LPP) is used in my bike for the magnet sensor of the back wheel so i’ve connected it to the High power port (HPP).
If you need further info just drop me a mail theray2189@gmail.com . I’ll try to help you to set things up if needed.