WC_Geolocation not found inside plugin

I suppose that the problem is because your plugin loads before Woocommerce plugin.

You should use it after Woocommerce is loaded, you have a hook to know that: woocommerce_init

Here you have a example to make a plugin of woocommerce:
https://www.skyverge.com/blog/creating-custom-plugin-for-your-woocommerce-shop/

I hope it helps
Regards.