I am sorry to have to disapoint you.
WebGrab+Plus is not available for Odroid C2, because it requires Mono, and I have not been able to build Mono for the aarch64 architecture, ie the Odroid C2 project.
In summary: the versions of Mono that support aarch64 do not cross compile for LE; bug tickets have been submitted, but to no avail.
Moreover, Odroid C2 does not provide docker, so that is not an alternative.
If I could bring Mono to Odroid C2, I gladly would.
Thanks for the response and info.
There is a thread in the main LibreELEC - Kodi Project thread on the odroid forum here
In this thread a user created a LE build with docker included for Odroid C2.
So maybe there is a chance to make webgrab++ for docker on the C2?