Capture One can read GPS location data from an image. This information is available in the Metadata tool:
You can also click Show on map/Open in browser, and it will show its location in Google Maps.
You can also filter for images that contain GPS data by creating a Smart Album with the Geotagged>is true criterion:
The same goes for the images that do not contain any GPS data — you just need to change the criterion to Geotagged>is false.
Note: GPS data cannot be added to an image at the moment. To modify GPS data for a single image or in batch, consider using third-party tools like EXIFTool.