Cloudfront caches content at edge locations near users whilst Accelerator routes requests to the nearest endpoint to the user.
GA is similar, but more like a global anycast routing layer/load balancer. You can have multiple backends, different regions etc, use a single public GA endpoint, and GA will route the request to your nearest backend.
You could use a GA endpoint as an origin for Cloudfront, I guess, to keep all traffic as near to the client as possible.