Possible to copy from a 16GB SDHC to the onboard 4GB eMMC?

I recently did a fresh install of bone-debian-10.4-console-armhf-2020-05-18-1gb onto a 16GB SDHC. Only using about 1.6GB of the space. Is it still possible to copy the SDHC to the eMMC even though it is only 4GB? I know it can be done before running “grow_partition” to expand the SDHC from 1gb to 16GB but can it still be done?

The official script uses rsync, so the size of the partition doesn’t matter, just the actual size of used data.