question

Load output, do they mean a shunt?

No.

Smaller Victron MPPTs have a dedicated output labeled "LOAD" (besides the Battery and PV terminals).

Those lines you quoted from the manual are about that LOAD output.

Is it possible to output this information to some software on my PC?
(Namely Open Plotter on a Raspberry Pie)

I don't know if that's possible.

You can use a VE.Direct-USB interface and VictronConnect software on a Windows PC.

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The ready made option for monitoring any Victron system is to use a so called GX device (such as Cerbo GX).

But you can make your own GX device using a Raspberry Pi, on which you install Venus OS (from Victron).

https://github.com/victronenergy/venus/wiki

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If you do not already purchased the MPPT, make sure you get a "Smart" Solar MPPT (not a "Blue"Solar MPPT).

For Victron equipment, "Smart" denotes built-in Bluetooth (not "Blue" as you might expect; "Blue" is much older naming).

SmartShunt also has Bluetooth.

Having such a pair you can access them with a phone (via Bluetooth), so maybe you don't need any other display.

Also with both having Bluetooth, you can use something called VE.Smart Networking:

https://www.victronenergy.com/media/pg/VE.Smart_Networking/en/index-en.html

Note:

If you include a GX device in your system, then do not use VE.Smart Networking, too.

A GX device gives you much more, but VE.Smart Networking has no additional cost (if using the correct components).