You could try rpi-clone Here. It uses rsync which I believe is installed already on LE. It can be run standalone in the home folder as ./rpi-clone. (No need to copy to /usr/local/sbin as in the install instructions)
I haven't tested it on LE yet but it works on Raspbian and has the added bonus that the system doesn't have to be shutdown.
I just used this script to clone my LibreELEC 9.2.8 micro SD card on rpi2. This project forked from the one mentioned by Iridium and was tweaked specifically for LibreELEC. I had to install Network Tools (Addons->Install from repository->LibreELEC Addons->Program add-ons->Network Tools) to get the required rsync tool.
I put the command in a backup.sh script so I don't need to remember the arguments next time I use rpi-clone. I only had one destination micro SD card in a USB adapter so destination "sda" might be different for you if you have multiple destinations (sda, sdb, sdc...). It's fast (partitioning can be skipped if destination partitions are identical) and only content is copied not empty sectors. Also the system doesn't have to be shutdown as mentioned by Iridium.