Thank you for posting the question here!
Unfortunately my guess is the USB2-OTGE100 Ethernet adapter wouldn’t work with the Galaxy S3.
Basically Android doesn’t allow users to install the device driver. If we wanted to connect any external device to Android tablet/smart phone, the device driver has to be built-in in the tablet/smart phone when they were shipped from the manufacturer. It all depends on the manufacturer or model if the device driver was built-in and active.
Since most of the time there wasn’t any information what kind of device drivers are built-in to a particular Android model, only way to find out if an external device works or not is actually testing it.
We haven’t tested nor heard back from our customers about Galaxy S3 yet, and as far as we know, almost all the Samsung Android devices don’t support (don’t have the driver of) this adapter.
Sorry about this bad news, but hope this help! If you have any further questions, please do feel free to contact us at firstname.lastname@example.org at any time.
Thanks again for posting the question!