In The Martian, the hermes ship used to go between Mars and the Earth used this method. In the hail Mary Project the ship split in two halves joined by cables to replicate earth gravity, by separating the two halves by large distance.

It’s a Sci fi concept so far, there must be a reson it’s not implemented.

In my experience it works across circuits, but speeds aren’t that great. Just connect them to the same outlet first for pairing. I’ve heard about this method working between apartments too.

Repeaters can add fuel to the fire if there’s already a lot of access points around. Especially on 2.4ghz which has limited number of channels. It can be helped by reducing the transmitting power on all devices.

Id rather recommend the wall plugs (they connect to wall power socket and transmit Internet over power wires via RF), if you can’t run Ethernet.