[WP Smush Pro] Smush an image before being uploaded to Google Storage or an image already there

Currently with the WP-Stateless plugin https://wordpress.org/plugins/wp-stateless/ if used as just a cdn I can smush the images since they are stored at the local wordpress install and on Google Cloud Storage. When WP-Stateless is used in the Stateless mode which uploads the images directly to Google Cloud Storage they are not smushed on upload and if I try to smush after upload it says not found since it is in Google Cloud Storage and not on the local server.

So I guess it really comes down to WP Smush Pro working with Google Cloud Storage since I know you do have support for Amazon S3. That or the option for WP Smush Pro to work with the WP-Stateless plugin by smushing before uploading or something like that.