Interesting strategy mate! Any links on how to do that? I've googled a bit but haven't find anything on this!
Yes check this out. What you'll have to do is build the aws sdk into a single javascript file that runs as a Web Worker. These are distributed to over a 100 servers worldwide. Then you would want to invoke the Lambda function from the worker, link below. You could potentially distribute this further by invoking a Lambda function geographically close to that specific worker. But this setup will be very fast already.
https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/Lamb...
If anyone is up for swapping ideas, I made a GitHub repo: