Is it safe to replace power cables to hardware with third party and different lengths power cords?

Yes you can replace the cable only some hardware vendors might have an issue if you remove the plug or make the cable shorter.

The figure 8 cable should be standard and should therefor not use less or more amps than specified.

In short you should be save to replace the cable with a shorter one.

DirkMare

I would agree with DickMare but add the specification that the replacement cable should be of the same or physically larger (smaller number) gauge wire.  Alternatively, you could read the specification on the cable for Amperage and make sure that new replacement is the same or higher.  This is NOT the same as the spec for the device itself, which will be lower.

you can also cut the cable to the lenght needed, and resolder the wires- putting heat shrink tubing over them
but YES you can safely replace the cable with any shorter one

"to confirm that is safe to use a power cable that can provide more amps than the hardware is requesting"
All cables are rated to more than the hardware uses.
 
The 2 Prong Power Cord / Cable is commonly used for printers, laptop, and camera AC adapters and are typically rated at 6 Amps 125 Volts.
The Amp and Voltage rating for the cable is printed on the plug (hardware end).
The wire gauge may be printed on the cable and will increase for longer cables.

Choose a third party cable that has the same or a higher amp rating.
I have looked at several that I own and regardless of length, all are rated at 6 Amps 125 Volts.

just to be complete, in Europe they are 2.5 A/250 V

Just to be pedantic I think you'll find that IEC 60320 C7 and C8 are rated 2.5A wherever you are in the world since it is the thickness of the copper that defines the current rating and the thickness of the insulation that defines the voltage rating. It is of course possible to have cables and plugs/sockets that have individual ratings that are higher or lower than the IEC spec.

Exactly what I was looking for, thank you!