The error in the log indicates that the method is called, so it's fine.
To build with C3 you need to export your project for Cordova, then unzip the exported game and edit two files - config.json and config.xml
See how other cordova plugins are configured there and add "cordova-plugin-device" the same way, preserving the correct formatting!
After that add all files back to ZIP, open Export Manager in C3, load your updated zip there and click "Build application" icon.
This will only work if cordova-plugin-device plugin is whitelisted in C3, I am not sure if it is.
Thanks, I will check how to edit the xml because I used to did on Construct 2 but know the format has changed.
Yes! I checked here: https://www.construct.net/en/forum/construct-3/plugin-sdk-10/build-server-cordova-plugin-149266 and cordova-plugin-device is there!
About removing the plugin references, it wasn't working haha but was a good point. Possible because when you add the plugin it needs to add the Admob ID.