Firstly I like to say I dont watch TY so I am not planing to record tv shows.
I am using my TV as monitor for nearly everything and I like to take screenshot or even record small videos of gameplay from Nintendo classic mini or PS2.
I have done some research and I can only find app that records show or external hardware like elgato, but I dont have the economy for that kind of hardware. I also did some research on if it was possible to make a raspberry pi a video capture device with a hdmi input but that option is also fair expensive because of a special hdmi to csi-2 bridge chip I would need to import.
I also learn that I could plug a usb stick for extra storage into the tv but it would be unreadable on other devices so I quickly skip that option.
I hope someone have a answer. It is just for a home project to keep my mind sane during these lockdown times. Thanks for your time.
PS. my tv is a KD-55xf9005 running android version 8.0
Have you considered just getting one of those cheap $10-$12 HDMI USB capture card sticks ?
They output 1080p and are surprisingly not bad.
I bought one late last year to play with. I've used it to capture the screen from both my Nvidia Shield and my Fire Stick 4K.
It should work on your nintendo classic device if it has HDMI. Just plug the console's HDMI into one end and then plug the USB into your PC. You can then use free software like OBS to view and record it.
They look like this:
https://i.imgur.com/qZ70vku.jpg
You can also get a USB 3.0 1080p60 version for a bit more. That's the one I have. It was like $13 when I bought it.
Edit: I should mention that I bought mine from AliExpress.com. It came from China and took about 3 weeks.