Sending snapshot to remote only

For some nocow subvolumes I like to avoid snapshots while still keeping snapshots on the remote backup device (nocow subvolume for Virtual Machines).
Snapshotting drops the benefits of nocow as said in the btrfs FAQ, snapshots will increase fragmentation again:
https://btrfs.wiki.kernel.org/index.php/FAQ#Can_copy-on-write_be_turned_off_for_data_blocks.3F
` COW may still happen if a snapshot is taken. `

Snapshotting to a remote btrfs only is not possible without creating a snapshot and sending. Then sending-on-the-fly is not supported.

Actually fragmentation happens only after the snapshots was created. It could be possible to create the snapshot, send it to remote and then delete it locally, all while the Virtual Machine is offline.
But creating the RO snapshot is done without delay, then sending, then deleting the local one. That is like sending-on-the-fly. Could you add this feature in btrbk? As it knows itself which and when the snapshot was sent so it can delete in locally, like preserve 0.