The setup I was focusing is creating a meaningful bash like script that runs when the URL is shared to Termux. I have also set up ways certain sites to have their audio stripped from the video, using ffmpeg and while basic, it does take about a couple hours to get things setup bug free in a way that's easy. Easy as in a two click, share -> termux and then just letting it run and it'll finish. And as other have mentioned, getting storage permissions right.