What would it take to add physical switches to my network? Could I use 4-pole switches on 4 out of the 8 in twisted pairs.

I like to disconnect my wired LAN computers while doing offline work, mostly for security reasons, but sometimes I exchange files between them. When I disconnect the power to my network switch I lose the whole network, no PC to PC exchange, and my Roku doesn't function.

Instead of unplugging each CAT 6 cable separately, constantly, my desire is to make a control panel where all connections to the network switch can be shut off independently. When I need certain network functionality I can specify what is connected to where.

To kill all traffic I'll use a 110v switch on the power adapter to the network switch. For traffic between PC's I want to shut off the connection from the network switch to the modem/router in the basement. Other times I'll allow my Roku to access the internet while editing video on 2 PC's offline (no exchange between them).

I'm not in the main building, so I have a single CAT 6 line running here, about 200 feet long. I don't want to bury another cable just for my Roku, although that would help. 

So, there are 4 twisted pairs of wires in network cable. How many wires out of the 8 need to be disconnected (switched open) to stop all traffic? Could I use 4-pole switches on all solid-color wires for example?

My time of internet searching for answers hasn't been fruitful so far, most of what I've seen are ads for network switches.