I know nothing about KVM switches, but they seem to be what I need to easily swap between my home computer and my work laptop on my HDMI Monitor, Keyboard, and Mouse.
I bought https://www.amazon.com/gp/product/B07M66SD79/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1 but when I swapped to the MacBook Pro which is USB-C only nothing worked. I'm currently using it for the Mac Mini, but I need a solution that actually lets me switch between both.
I'm not really interested in having it act as a power supply for either because those are seem wildly expensive and I already have power supplies for them.
If I have to: https://www.aten.com/global/en/products/usb-&-thunderbolt/docking-switches/us3310/ seems as though it would work, but they seem focused on having a latop and smartphone plugged in. Not a laptop and mac mini. Power supply seems concerning here.
Best Answer
Keyboard and mouse only
Only taking into account the keyboard and mouse you can perhaps use software to share those with multiple devices instead of hardware.
Synergy can do this, but is currently paid. The last free version is 1.8.8 and is available at sourceforge.
Screen, keyboard and mouse
Alternatively you can access one machine (e.g. the Mac Mini) via remote desktop from the other (e.g. the MacBook Pro). If they're on the same local network and depending on the use case the speed should be very acceptable.
I'm not affiliated with Synergy, just a happy user.