copy btrfs filesystem from one disk to another smaller one

copy btrfs filesystem script.txt

sudo mount -t btrfs -o subvolid=0 /dev/sde /mnt/disk

sudo btrfs subvolume list -qu --sort ogen /mnt/disk
ID 257 gen 69317 top level 5 parent_uuid - uuid 5c2a18a4-3b47-f64e-afa9-34e75535a728 path rootfs
ID 339 gen 61638 top level 5 parent_uuid 5c2a18a4-3b47-f64e-afa9-34e75535a728 uuid 64cc0383-d122-a24f-a2c3-6f58839b52db path snap-rootfs-buster

sudo btrfs property set -ts /mnt/disk/rootfs ro true
sudo mount -t btrfs -o subvolid=0 /dev/sdb /mnt/usb

sudo btrfs send /mnt/disk/rootfs | sudo btrfs receive /mnt/usb/

sudo btrfs send -p /mnt/disk/rootfs/ -c /mnt/disk/rootfs/ /mnt/disk/snap-rootfs-buster/ | sudo btrfs receive /mnt/usb/

sudo btrfs property set -ts /mnt/disk/rootfs ro false; sudo btrfs property set -ts /mnt/usb/rootfs ro false

sudo btrfs subvolume get-default /mnt/disk/
ID 257 gen 69317 top level 5 path rootfs

sudo btrfs subvolume list /mnt/disk/ -a -p -t
ID	gen	parent	top level	path	
--	---	------	---------	----	
257	69317	5	5		rootfs
339	61638	5	5		snap-rootfs-buster

sudo btrfs subvolume get-default /mnt/usb/

sudo btrfs subvolume list /mnt/usb/ -a -p -t
ID	gen	parent	top level	path	
--	---	------	---------	----	
299	162	5	5		rootfs
356	163	5	5		snap-rootfs-buster

sudo btrfs subvolume set-default 299 /mnt/usb


#more info at:
#https://superuser.com/questions/607363/how-to-copy-a-btrfs-filesystem
#https://github.com/mwilck/btrfs-clone