What does "input port" mean...;-) You can use any port as a connection to your 10G network and then, for example, use the 1G for a printer...
Or this switch is used within four computers/NAS to be able to quickly deliver data to each other and the 1G is then used to connect to a 1G network (which is probably most common...).

For example, I have my telephone on the 1G port of this switch and a PoE feeder in between. Works fine and as an uplink to my 10G network I use one of the 4 10G ports...;-)

Port 1 is blockable and or combo it's illogical, you just need to supply it with 120watt poe++ and ploquing it to use the 4 other ports.

As the others have stated, use one of the four 10Gb ports as input and the 1Gb port as an output for say a printer or other 1Gb limited device. The PoE of the 1Gb is in this instance superfluous.

I'm wondering the same thing because the XGs are multi-gateway 10g max devices for connecting switches together, not PCs.