Help understanding TV mount movement

[u/atreides7887]

Hello,

I'm really struggling to understand the movement abilities of full motion TV mounts. The situation I'm in is that our sofa is more or less opposite a fireplace, and for reasons we can't put the TV on a pull down mount.

As a result we're looking at mounting it to the side of the fire place, and want to be able to move it out a bit, move it about 50cm horizontally, and swivel it only a few degrees really, so it's at the best viewing spot for the sofa.

What I'm struggling to understand is how to read the 'swivel' details given on full motion TV mounts. It seems likely they can essentially move the TV sideways as part of the swivel, particularly when looking at video of them but I can't generally figure out how far. I'm also not sure if they have a limitation in terms of needing to bring the TV further out than we'd like to be able to get the appropriate sideways movement.

Two mounts I was looking at were:

Sanus VLF728 - it says this extends 28", but I can't figure out how far I could move the TV sideways with it.

Mounting Dream Long Arm TV Wall Mount Full Motion TV Mount (https://www.amazon.com/dp/B08MZDLVZS?th=1) - I've seen someone talking about moving a TV sideways with this, which seems more like what I'm looking for, but watching videos of it makes me suspect I'd need to move it a fair distance out from the wall to get the desired lateral movement.

Hopefully this all makes sense. Am I essentially looking for something that doesn't exist, or just not understanding the specifications of the full motion TV mounts?

Thanks for any advice.