https://www.amazon.com/TP-Link-AV60..._r=D8V78YMWCXD9QQB4PBH1&qid=1608954635&sr=8-3 this is the sort of thing i used to use. i have tried them in old houses no problem. no guarantees but it should work. We have real solid walls here that are like a foot thick so wifi isnt that great, as long as the same ring main connects everything it should work, you only ever see the one access point too, it just clones the main credentials so its not like you need to connect to a different wifi, it should just auto navigate things like your phone between hotspots like nothing
you will want a full starter kit and then however many "wifi addons" you think you will need, i even got one from a different brand and it had no problem doing its job, one of those is the master tho and one the slave unit, the master connects to the router and your socket in the living room and the slaves all send the signal thru the cable, they act like wireless repeaters on a hardline, you can even connect a lan cable to the repeaters if you do prefer a more reliable connection. i highly recommend them
"If I don't want to go the power line route, can you suggest a particular Archer and non-Archee router? " having never used one i cant sorry, not something iv used or have any kind of experience with im afraid