Bottom line: very limited BT headsets work with this model watch. For sure the 300€ Beoplay E8 don't pair. I am not standing in a remote field or forest to be the first device to pair with it and turning off each time BT on any other device/phone to get the pairing.
There's a good reason for the significant price drop of these models. To good to be true TOMTOM! Try harder next time.