So I made this thread around 4 years ago: https://www.bleepingcomputer.com/forums/t/504301/ethernet-splitter/
So I'm actually in the same situation as I have been, and I was looking into some powerline adapters, mainly this one: https://www.amazon.com/TP-Link-AC750-Extender-Powerline-TL-WPA4530/dp/B01CVOM140
Now, I'm a bit wary on how this can work. It does look like there are a multitude of good reviews, however, I have also heard that it does mainly depend on the electrical system in your house, and even then, that in some cases there are frequent drops and that the wifi signal isn't as great as it touts to be.
I have these:https://www.amazon.com/gp/product/B00Y3QYTS6/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
I do not use it to extend a WiFi signal, but rather to bring an ethernet connection to a Tivo Mini at a second TV. I was using an Apple Airport Express that was extending a WiFi signal from an Airport Extreme...and then using the ethernet port on the Express for the Tivo Mini (the Tivo Mini requires a wired connection). The original setup mostly worked OS, but I was having some issues with the Tivo Mini losing the connection to the main Tivo device. The new setup with the powerline adapters seems to be working better to date, but I have not been running them that long...and I don't use that second TV much unless I have guests staying with me, so it has not really be tested much.
This does not directly help you, I realize, as it is not a one to one situation.
As I understand powerline adapters, the big thing is that everything needs to operate off of one circuit breaker/fuse box, but they don't need to be on the same circuits. That is certainly the case in my house. The two powerline adapters are NOT on the same circuit in my house.
I'm mainly wanting to purchase one because the wifi signal in my room is horrid, and running another long cable under the house isn't an option, sadly. Just the fact that this uses data transmitted through electrical wiring rather than traditional networking means has me suspicious.
Is there any other alternative to this? I tried to set up my wired PC as a hotspot using a wireless adapter, but I can't get that to work reliably at all. What I'm specifically looking for is something I can plug my one ethernet cord into, and have that be able to be split into multiple ethernet cords AND a wifi hotspot. Does a switch meet all of this criteria?
Thanks again for the help.
You can use a switch to "add" additional ethernet ports at the location of your wired PC. Then you can plug one ethernet cable from the switch to the wired PC and use another ethernet cable for a WiFi access point, WiFi extender, or wireless router that you operate in "access point" mode. You can get a 5 port switch for about $20 (US). The cost of the access point, extender, or router will depend on what you select, but you are likely looking at at least $50 to $100.