Hello,
I continue this discussion, since I'm having the same problem/question:
I'm trying to install the Arduino 2.0RC5 IDE on my school PCs (about 50 machines) silently, using the MSI installer and a BATCH file to run the commands:
START /WAIT "" MSIEXEC /i "arduino-ide_2.0.0-rc5_Windows_64bit.msi" /qn ALLUSERS=1
With this command, the IDE is correctly deployed to the machines, but every different user that logs on the machine, at the first execution of the IDE needs to download all the basic cores/libraries, that seems to get saved into the APPDATA folder of every user:
C:\Users\[username]\AppData\Local\Arduino15
Unfortunately, this is not possible in our case, since the Appdata of the network profile of the students is not large enough to contain all the hundreds of MB (>300MB) that are saved there! 
Is there a way to install the IDE (completely) locally on the machine, which I thought was the case with the ALLUSERS=1 switch, maybe downloading at least the basic boards/libraries on the machine itself (it's ok if any future additional core/library chosen by the students goes into their profiles, but not all the hundreds of MB of the default installation)?
Thank you very much for any advice!
P.S.
I already tried, using arduino-cli during the installation, to issue the command
arduino-cli.exe core install arduino:avr
but unfortunately it doesn't seem to work... 