flash internal eMMC without host PC

is it possible to flash the Jetpack image to internal eMMC without host PC. perhaps by the jetson itself with image from external USB stick?

“flashing” is not possible without an x86_64 Linux host. You can use standard backup/restore Linux tools for updating the root partition, e.g., rsync. Updating hidden partitions is a whole new level of operation compared to updating just individual files on the root partition.

To use the JetPack installer front end you must use Ubuntu for the host, there is no alternative.