Dietpi & NOOBS

Hi everyone.
I’m new to Raspberry world.
I’ve just bought a pi4 board (2gb) and installed Raspbian Lite via Noobs (main OS), together with LibreElec and Lakka and I find very useful the NOOBS multiboot options to change OS on boot without changing SD card.

Now I’d like to install Dietpi which is unsupported natively by NOOBS, to keep options to change OS at boot time (very useful to me)
Is there any way to put Dietpi in NOOBS?
I googled something on noobs docs, but it’s not very clear to me…

Thanks for any help!