Use Case: Location Specific Users

Given a user's followers, I'd like to be able to know their general location. Country is fine.
Is there a tool or process for this?

I don't think there is any tool to know the location of the followers. You can only guess on the base that someone's most of the followers can be from his own country.

Follower's location information on YouTube is often incomplete or inaccurate. Many users choose not to share their location publicly, and even if they do, it might not be their current location. Attempting to use tools or processes to achieve this would be unreliable and raise ethical concerns.

If you must get the location you may want to ask the user directly or use location-based targeting tools.