I have a Sony SBH52 Bluetooth Handset and I discovered a way to send messages to it from Automagic. It should also work on SBH50 since it's almoust identical to the SBH52.You have to install Tasker - Smart Notifier after that, in your Automagic flow add a new plugin action, select the "Tasker Smartwatch Notifications" plugin, press Configure and enter something for the Title and Content.
Ignore the "Action1/Action2/Action3" as those do not work (those where designed for the Sony Smartwatch and the SBH doesn't have the functionality).
With this method i can show the battery status, weather and other flow statuses dirrectly on the SBH52 so i can see them without having to open the phone and check there.
I hope this is of some help for other users of the SBH50/52.
P.S. the messages are not deleted from the SBH50/52 until you delete them, so don't send too many messages. Also, i didn't find a way to "clear all notifications" from the SBH, maybe somebody else knows of a way.