Some clairification needed on the License

Hi, 

I'm working on linux with the MediaServerStudioEssential.

There, it seems pretty clear that if you need to accelerate HEVC you need a commercial license, correct me if I'm wrong please.
Instead, if you are just using the hardware acceleration on h264 the is no need of a commercial license.

Please keep in mind that we use a custom build of ffmpeg for transcoding.

So it seems that we just need the media SDK and not the Media Studio Server.
The Media SDK 2019 Q1 on git hub come with a nice MediaStack.

We are guessing what kind of license do we need to use ffmpeg with hardware acceleration for h264,MPEG2,HEVC using the MediaStack on github.
I read the License that comes with the media stack but we'd like to be really sure.
Please consider that transcoded videos are for commercial use.

BR
Francesco