I replaced my home plug av2 adapter with g.hn ones a year or two ago, and it has been much better.

Lower latency, more stable, and higher bandwidth. (The av2 ones would just drop out for 90-ish seconds a few times a month, which was quite annoying).

It's interesting the article talks about home plug av2 and g.hn coexisting, when my experience has been that g.hn powerline is much better, and it feels like g.hn is generally perceived as a successor to av2 in the UK.

Edit: also, I'm in agreement with other folk in that point-to-point wireless is the solution I most often see used in that case, or sometimes fibre.

Edit2: and it's also probably the cheapest one to test. If it's not good enough, then you know you're looking at wireless or fibre.