I have a TV box with 1.5 GB lpddr3 that has been running Manjaro Arm without any problems for a long time.
I used this TV box to add lpddr3 support to the dram driver many years ago. You can get the latest patch for 6GBIT lpddr3 support here:
https://github.com/iuncuim/manjaro-h616/blob/main/uboot-t98-h2b-lp3/0007-shrink-ram.patch
I added a patch that activates the gpu. https://lore.kernel.org/linux-sunxi/20250706025625.2707073-1-iuncuim@gmail.com
A ready to install kernel is available for manjaro. But it's worth realizing that without output it will be useless at the moment.
Owners of h616/h618 boxes can try warpme's miniarch (from github), its distribution contains the necessary patches for h616/h618, like ddr3/lpddr3/lpddr4 support, hdmi, audio, 100mbps ethernet and etc