I’ve got it up and running in our own source version of the engine. It does exist as a separate plugin to use with any non-nvidia branch of 4.26, you just have to go to their branch to pull the plugin folder itself.
As far as the watermark, there is the DLSS SDK - DO NOT DISTRIBUTE watermark that still exists when testing. I haven’t gone through the process yet so I’m not sure what the requirements are to get a shipping DLL, but if I find out I’ll report back.