That's definitely doable, yes
#POST request inside a worker (not working)
raw trail
My guess is your cors error means your worker is on a different domain to the browser?
If so, you'll need to send cors headers in your responses from your worker, same as any other server
Something like https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS#the_http_response_headers might help you out
Your worker will need to respond with cors headers (see the link above) so that your browser doesn't block the request
You can return whatever response you want
For example you might want to return something like new Response(null, { headers: "Access-Control-Allow-Origin": "*", status: 204 }) if you don't care about what the worker responds
(204 means an empty response)