Air-gap installations and nerdctl

I was successfully using the air-gap ‘ deploy images method’ for my application images.

However, I moved from docker-desktop to rancher-desktop (uses nerdctl) but now the ‘nerdctl save’ command creates a tar file in a format that k3s cannot read (the tar has the ‘blobs’ folder). Previously, with docker, the tar was properly readable (the tar has the ‘repositories’ and ‘manifest.json’).

How can I instruct k3s to use the tar images in its ‘\var\lib\rancher\k3s\agent\images’ folder to read the ‘blobs’ format?
Or the other way around , to have ‘nerdctl save’ create a tar with the ‘repositories’ and ‘manifest.json’ format?