For images, on Android you could use Imagepipe.
Once you’ve set it up, simply “share” the image to Imagepipe, it does its thing then automatically passes it on to whatever app you want - for example a messaging app for you to send on to others (it stores a copy of the image minus its metadata in an Imagepipe folder in your gallery for ease of access should you need it again).
For video, from memory I think mp3tag for Windows/Mac can remove metadata from some video formats
Simplest option is probably speak to sales staff & specifically ask about the set up process. It might be worth phoning a couple of reputable TV vendors as they may have more understanding than the spotty herberts in the sheds at the local retail park.
I last bought a TV outside of your preferred time frame but back then Panasonic made, what for my needs, was the best panel for the price & didnt insist on having internet in order to set it up (no idea whether this has changed with current generation models)
It doesnt help with your hdmi concerns, but what about blocking the TV at router level or restrict it by putting it on VLAN/guest network then disconnecting it from the internet forever once set up.is complete?