OK Google isn't working in my new Fossil Gen 3 Explorist

Question

I have tried restarting the phone and watch multiple times. I have also did a factory reset to my watch two times. I have uninstalled Google app in my phone and reinstalled the same. I have retrained the voice model for 'OK Google' identification. I have installed the new 'Assistant' app from Google. Everything works fine while doing a long press of power button and the issue only comes while identifying the voice in watch. In phone, all voice related commands work fine.
Phone: Moto X Pure with Android Nougat
Android smart watch: Fossil Gen 3 Explorist with Android Wear 2.0

NonsensicalNick · Accepted Answer

No worries, just wanted to make sure you still needed help. 
It may be worth resetting the watch and starting from scratch. Follow these instructions:
On the watch:
Settings, Un-pair with phone. (Old release of AW may say Factory reset.)
Do not set up the watch yet.
On the phone:
In Android Wear use the Disconnect... option.
In Android Wear, use Settings, Device settings and touch the watch name, Touch FORGET WATCH.
Settings, Bluetooth. If you still see the watch, touch Forget... the watch so it no longer appears in the list of paired devices.
Settings, Device, Apps, select Google Play Services. Clear cache and Clear data. Uninstall updates.
Settings, Device, Apps, select Google App. Clear cache and Clear data. Also Uninstall updates.
Settings, Device, Apps, select Android Wear. Clear cache and Clear data. Also Uninstall updates.
Play Store, Apps, My apps, touch the Update all button. 
Let all updates complete. This may take several hours. The best thing to do is to put your phone on its charger overnight, with the phone having a steady WiFi Internet connection. Double check the next morning by going to My Apps again.
Shutdown (do not just restart) and turn back on. 
Now set up the watch as if you had just un-boxed it.
Let all updates complete. This may take an hour or so. If your watch is one or more major releases behind it may take several hours. The best thing to do is to put your watch on its charger next to your phone on its charger, with the phone having a steady WiFi Internet connection.
Reboot watch and phone.