Do you need additional software for AV1 codec to work on Windows or Linux?

[comsyspro]

On Windows and Linux you install the GPU driver. Do you also have to install additional software codecs for using AV1 codec like this here?

AV1 Video Extension
https://apps.microsoft.com/detail/9MVZQVXJBQ9V?hl=en-us&gl=US

Or is the AV1 codec fully implemented in sunshine/moonlight and no other software besides the GPU drivers are needed?