Talking about the law is a bit far surely? Nobody is going to sue over this are they
If opponent asks you not to post, then just respect that. He could be embarissed by his bad play, or have a sneaky strategy he wants to keep to himself.
Yeah I know there are logs so it doesn't really matter, but if he asks I cant see why not.
But yes, there is the sympton that being recorded makes you play differently, I know if you told me I was being recorded I would play a lot slower and double think everything to make sure, but then im not as good as you and am quite self concious.
So I would record them for your own records, and then if you want to post them afterwards, ask the person after the match, or near to the end would be better in case they quickly resign