Hello @wlwfuture
Smush does not create any new thumbnail versions nor does the actual resizing. There are some default image sizes from WP and then themes/plugins can create more sizes. Then when an image is uploaded to the Media library it is WP itself that creates the thumbnail versions of that image.
Now Smush by default will optimize (shrink its filesize, not dimensions) all of the thumbnails versions.
For including the original full-size images as well, just enable the Compress uploaded images option in Bulk Smush settings.
Let us know if more help is needed.
Thank you,
Dimitris