in ubuntu (online or offline), make the download script:
sudo apt-get install [package name] --print-uris -qq | sed -n "s/'\([^ ]\+\)' \([^ ]\+\) \([^ ]\+\) MD5Sum:\([^ ]\+\)/wget -c \1/p" > script.cmd
run it in online ubuntu
sh script.cmd
zip it for convenience
tar -cvf [file name].tar.gz *.deb
move it to the computer without internet access by any means!
unzip it
tar -xvf [file name.tar.gz]
and install it all
dpkg -i *.deb
credit: this answer in SO