If your boxes are modern enough, USB-C display/thundebolt connections work pretty well and are easy to connect and disconnect. Not sure if your boxes will support dual monitors or even usb-c displays.

Since you don't care about simultaneous use - what's the problem with a USB keyboard and mouse hooked to a usb hub, and a couple of hdmi or displayport connectors to your monitors? Plug in the two monitors and the hub and you're done.

Dell WD19TB I do this at my office. Just make sure it's got the latest firmware on it. That's a easy update from any windows machine. Both systems will need to support thunderbolt.

Do you want to run BOTH monitors off of either computer, or just one for each, and share the mouse/keyboard/speakers?  Also, what type and number of inputs do you have on the back of each monitor (and laptop)?

For the speakers, what type of input do they take?  3.5mm, USB, etc.  For 3.5mm, you can use a cable splitter, around $5 on Amazon.  

For the mouse and keyboard, a simple kvm switch will do the trick.  Macs tend to have problems sharing video connections through kvm switches.  If your monitors have multiple inputs, it is probably simpler to run inputs from each laptop to the monitor(s) you want to use them with, and let the monitors detect which is being used.

Mike

Sounds like your wife's laptop doesn't have thunderbolt, so you'd be stuck with USB-C/thunderbolt pc->dock display options if you wanted to leverage that.

Whether you'll be able to split screens depends on the resolutions you'll run them at, and if your wife's USB Type C port is really a USB4, or a USB3.2 with the Type C connector. Hers might only support a single 4k display, or require dropping to 30Hz to support dual 4K displays, while thunderbolt can handle dual 4K@60Hz and beyond.

That said, most more modern systems will fully support dual split desktop displays, with the limiting factor being resolution and refresh, and sometimes color depth. Even a 10 year notebook can usually handle dual screens at 1080p or 1440p.

I use a USB C dock, it can also just use USB 3.0

USB C will limit how much monitor you can drive. I found this out when I bought a 49" monitor. I think USB C will drive two 'quad hd' screens. You'll need Thunderbolt 3. I bought one of the new models of Plugable's docks that will accept either USB C or Thunderbolt 3.

The second limit with Thunderbolt 3 is the length of the cable. They're relatively short, and they are NOT USB C cables. Longer cables need to be 'active', or you'll lose bandwidth.

This is the one I got:


They go in and out of stock. The only thing I dislike is that the audio out is on the front, as if to be used with headphones. I plug mine into my desktop computer and route the audio out through it.

I just received a new Dell XPS-15 9500 with a 6 core 10th Gen i7, 32GB RAM and a 1TB SSD... and it's fuggin nice. It runs this bigass monitor nicely.

My USB C dock will push 5K x2